Difficulty
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Interactive practice · 10 questions on HTML, CSS, JavaScript, and HTTP fundamentals — easy to hard, with step-by-step explanations.
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Easy What does HTML stand for?
Answer: A — HyperText Markup Language
Easy Which HTML tag creates a hyperlink?
Answer: B — <a>
<a href="..."> makes a clickable link. <link> loads resources like CSS.Easy Which CSS property sets the text color?
Answer: C — color
color sets text color; background-color sets the background.Medium Which are valid ways to declare a variable in modern JavaScript? Select all that apply.
Answer: A, B, D
var, let, and const all declare variables (let/const are block-scoped).dim is not JavaScript.Medium Which CSS selector targets an element with id="main"?
Answer: A — #main
# selects by id; . selects by class.Medium An HTTP 404 status code means:
Answer: C — Not Found
404 = the requested resource was Not Found. (200 OK, 301 redirect, 500 server error.)Medium In JavaScript, which operator compares value and type without coercion?
Answer: B — ===
=== is strict equality — no type conversion. == coerces types first.Hard Which HTTP method is used to retrieve data and is idempotent/safe?
Answer: D — GET
GET retrieves data without side effects; POST creates/submits data.Hard What does this log?
console.log(0.1 + 0.2 === 0.3);Answer: A — false
0.1 + 0.2 = 0.30000000000000004.0.3, so the result is false.Hard What does typeof [] return in JavaScript?
Answer: C — "object"
typeof [] is "object". Use Array.isArray() to check for arrays.