Application Development - 1 · Quiz 1 · Jan 2026

**1. Find coverage time:** The client starts essentially at the tower and moves radially away, so it travels 4.5 km before losing coverage. At 180 km/h, \(t=4.5/180\text{ h}=90\text{ s}\). **2. Convert bits to bytes:** Data transferred is \(5\times90=450\) megabits. Since one byte is eight bits, \(450/8=56.25\) MB. **Answer: D — 56.25 MB.** **Convention note:** Mbps and MB use decimal mega units. Coverage starts at the tower, so use the 4.5 km radius rather than the full 9 km diameter. A: **Incorrect:** This does not follow from the specified bandwidth and 90-second duration. B: **Incorrect:** 450 is the number of megabits, not megabytes. C: **Incorrect:** This is about a factor of ten too small. D: **Correct:** 450 megabits divided by eight gives 56.25 MB.

**1. Resolve background specificity:** All three paragraphs match div p. The first also matches .highlight, which wins and makes it pink; the second matches #special, which wins and makes it orange. The third stays light blue. **2. Resolve layout independently:** The p rule sets display:inline-block. None of the other selectors changes display, so the paragraphs form content-sized inline blocks on the same line when the container is wide enough. **Answer: C — Inline blocks: Paragraph One pink, Paragraph Two orange, Paragraph Three light blue.** A: **Incorrect:** The colors are right, but the paragraphs need not appear on separate lines. B: **Incorrect:** The colors are right, but inline-block does not make each paragraph fill the line. C: **Correct:** This combines the correct pink/orange/light-blue backgrounds with inline-block flow. D: **Incorrect:** This ignores the higher-specificity class and ID background rules.

**1. Apply query defaults:** Requests 1 and 2 both give a=3,b=2,c=5. The extra d=5 parameter is never read. In both cases a+b=c, so the output is “Sum: 5”, label c. **2. Trace requests 3 and 4:** Request 3 gives (1,5,5): the sum test fails but a*c=b, so it prints “Product: 5”, label d. Request 4 gives (1,5,6), making the first test true and printing “Sum: 6”, label a. The mapping is 1-c,2-c,3-d,4-a. **Answer: C — 1-c, 2-c, 3-d, 4-a.** A: **Incorrect:** Requests 1 and 2 are valid, and request 3 prints Product: 5 rather than Sum: 6. B: **Incorrect:** Requests 1 and 2 do not produce Invalid Input because every converted value is valid. C: **Correct:** All four requests are mapped to their actual branch outputs. D: **Incorrect:** The unused d parameter does not invalidate request 2.

**1. Parse the source before starting Flask:** In Python 3, 0007 is not a legal nonzero decimal integer literal. app.run(port=0007) therefore raises SyntaxError before any server starts. **2. Choose the listed outcome:** No offered address serves this program as written, so choose “None of these”. Replacing the literal with 7 would request port 7 rather than the default 5000. **Answer: D — None of these.** A: **Incorrect:** No server starts, and app.run() does not configure HTTPS here. B: **Incorrect:** This would require first repairing the invalid Python integer literal. C: **Incorrect:** No server starts; 0.0.0.0 is also not the default bind host in this code. D: **Correct:** The Python syntax error prevents all listed application URLs.

**1. Filter the sequence:** reject("even") removes 10 and 8 from [10,3,9,8,15], leaving 3,9,15 in their original order. **2. Render each value:** Adding 2 gives 5,11,17. The whitespace-control markers join these values without separators, giving 51117 apart from surrounding template whitespace. **Answer: D — 51117.** **Convention note:** The triple-quoted template can retain a surrounding newline. The answer choices compare the non-whitespace content. A: **Incorrect:** This includes values inconsistent with rejecting even inputs. B: **Incorrect:** This does not follow the filtered sequence and addition. C: **Incorrect:** This is the filtered sequence before adding 2. D: **Correct:** The surviving values become 5,11,17 and concatenate as shown.

**1. Evaluate the exact comparison:** The Flask context sets user="admin iitm", while the template tests user=="admin". String equality requires the entire value to match, so the condition is false. **2. Render the else branch:** The root route exists and renders home.html, whose else branch displays “Welcome User”. **Answer: B — Welcome User.** A: **Incorrect:** The supplied value is not exactly admin. B: **Correct:** The false equality test selects this else-branch text. C: **Incorrect:** The root route is defined, so this is not a routing 404. D: **Incorrect:** The template has a nonempty else branch.

**1. Sort the numbers:** Jinja’s sort filter orders [5,2,8,1,9] ascending, giving [1,2,5,8,9]. **2. Render one element per iteration:** The loop emits five paragraph elements containing 1,2,5,8,9 respectively. The terminal prints the HTML source string rather than displaying a web page. **Answer: B — Five paragraph elements containing 1, 2, 5, 8 and 9.** **Convention note:** The choices suppress surrounding template whitespace. The loop’s whitespace-control markers remove spacing between repeated paragraph fragments. A: **Incorrect:** This preserves the unsorted input order instead of applying sort. B: **Correct:** This has the ascending values in five separate paragraph elements. C: **Incorrect:** The default sort order is ascending, not descending. D: **Incorrect:** The loop creates one paragraph per number rather than one paragraph containing their concatenation. E: **Incorrect:** Sorting this list and rendering its integers are valid operations.

**1. Match the requested path:** /post/abc123 must match /post/<int:post_id>. The int converter does not accept abc123, so this route does not match. **2. Check alternatives:** The other route starts with /profile/, not /post/. No route matches this request, so Flask returns 404 Not Found rather than invoking the post view. **Answer: B — Flask will return a 404 error because abc123 cannot be converted to integer.** A: **Incorrect:** The integer route rejects the noninteger segment before the view is called. B: **Correct:** The converter mismatch leaves the request without a matching route. C: **Incorrect:** The profile route has a different literal prefix. D: **Incorrect:** This is a normal routing 404, not a TypeError crash.

**1. Select diagnostic output:** curl -v enables verbose mode, reporting connection details and the sent request and received response headers, which helps debug an HTTP exchange. **2. Distinguish response inclusion:** curl -i includes response headers with the body but does not supply the same request-side and connection diagnostics. **Answer: B — curl -v <URL>.** A: **Incorrect:** -i includes response headers but is not the full verbose diagnostic option. B: **Correct:** -v enables the requested verbose request/response diagnostics. C: **Incorrect:** --headers is not the documented flag for this behavior; --header sets a request header. D: **Incorrect:** -X GET selects the request method but does not enable detailed diagnostics.

**1. Distinguish encodings:** UTF-8 encodes Unicode scalar values using a variable number of bytes; UTF-32 uses one four-byte code unit per scalar value. **2. Judge markup and styling:** Attribute names in ordinary HTML syntax are ASCII case-insensitive. Large projects generally benefit from reusable external stylesheets rather than duplicated inline styling. **Answer: A, B, D — UTF-8 is a variable-length encoding that can represent all Unicode characters.; In HTML, attribute names are case-insensitive.; UTF-32 is a fixed-length encoding where each character takes 4 bytes..** **Convention note:** “Character” here means a Unicode scalar value, not necessarily a whole user-perceived grapheme such as a multi-code-point emoji. HTML syntax is meant, not XML/XHTML case rules. A: **Correct:** UTF-8 can encode every Unicode scalar value using one to four bytes. B: **Correct:** Ordinary HTML attribute names are ASCII case-insensitive. C: **Incorrect:** Inline styles do not provide the usual reuse, separation and maintainability of external stylesheets. D: **Correct:** UTF-32 uses four bytes per encoded Unicode scalar value.

**1. Identify the usual architecture:** A web application commonly has a browser frontend, server-side logic and persistent data storage. The browser can communicate with backend APIs over HTTP. **2. Avoid universal claims:** Some applications run mostly on the client, but that does not mean all web apps need no server. A normal web application can be used through its URL without installing a dedicated desktop application. **Answer: B, C — Web applications can interact with backend services using APIs.; A web application typically consists of frontend, backend and database .** A: **Incorrect:** Many web apps require server-side processing, so “all entirely in the browser” is false. B: **Correct:** APIs are a standard way for the frontend to exchange data with services. C: **Correct:** These are common components, although every particular app need not use all three. D: **Incorrect:** A browser can access a web app without installing the app as native software.

**1. Read the invocation:** For an ordinary script command such as python app.py 12, Python supplies a list like ["app.py","12"] in sys.argv. Index 0 identifies the script and later entries contain its arguments. **2. Handle types explicitly:** Arguments arrive as strings. Numeric conversion, such as int(sys.argv[1]), must be requested by the program; it is not automatic. **Answer: A, B, D — **sys.argv** is a list containing command-line arguments.; **sys.argv[0]** stores the Python script name.; **sys.argv** elements are always interpreted as strings..** **Convention note:** For special invocation modes, argv[0] may be -c or an empty string; this does not change the usual script example. Code can also deliberately reassign sys.argv, so “always” refers to the supplied command-line representation. A: **Correct:** sys.argv is the list of command-line argument strings. B: **Correct:** In the script-running context, index 0 contains the script name or path. C: **Incorrect:** An argument that looks numeric remains a string unless explicitly converted. D: **Correct:** The command-line entries supplied by Python are strings.

**1. Identify the required links:** The three supplied dictionaries require visible names user_1,user_2,user_3 and links /show_users/1,/show_users/2,/show_users/3, wrapped in an ordered list. **2. Evaluate each construction:** Jinja supports both dotted dictionary lookup and bracket lookup. Direct indexing also works for this fixed three-item list. D obtains the final character of each supplied name, which happens to equal that user’s ID. Thus all four produce the required links for these data. **Answer: A, B, C, D — All four options work for the supplied three users.** **Convention note:** D relies on the naming pattern and is not a robust general ID lookup; C hardcodes the list length. A or B is preferable for arbitrary user data, but the question asks what works for the given list. A: **Correct:** The loop’s user.id and user.name resolve to the dictionary keys. B: **Correct:** Bracket notation reads the same id and name keys explicitly. C: **Correct:** The three fixed indices cover the complete supplied list and use its correct IDs. D: **Correct:** For user_1,user_2,user_3, name[-1] gives 1,2,3, matching the stated IDs.

**1. Add the border-box parts:** Under default content-box sizing, the declared width is the content width. Including horizontal padding and borders gives \(200+2(10)+2(2)=224\) px. **2. Keep margin external:** The 15 px margins lie outside the border box and do not alter its 200 px content width. Including both horizontal margins, the complete horizontal footprint is \(224+30=254\) px. **Answer: A, C, D — The total width including padding and border is 224px; The padding adds internal spacing inside the element; The border contributes to the total width in the standard box model.** A: **Correct:** 200 px content plus 20 px padding plus 4 px border equals 224 px. B: **Incorrect:** Margin is outside the element’s border and does not change the declared content width. C: **Correct:** Padding provides space between content and border. D: **Correct:** The left and right borders add to the outside width under content-box sizing.

**1. Identify missing keys:** The template requires name and count. substitute() raises KeyError if any required mapping key is missing, so A fails on count. **2. Compare the remaining calls:** safe_substitute() leaves a missing placeholder unchanged, so B succeeds with “Hello Alice, you have $count messages”. C and D provide both keys and produce “Hello Alice, you have 5 messages”. **Answer: B, C, D — out = template.safe_substitute({"name": "Alice"}); out = template.substitute({"name": "Alice", "count": 5}); out = template.safe_substitute({"name": "Alice", "count": 5}).** A: **Incorrect:** substitute() raises KeyError because count is absent. B: **Correct:** safe_substitute() retains $count instead of raising KeyError. C: **Correct:** Both required keys are present, so strict substitution succeeds. D: **Correct:** Both keys are present, and safe_substitute() also succeeds.