Performance Measures - Study Mode

[#66] What is the purpose of the advanced mode in the Closure compiler?
Correct Answer

(B) Renaming the variables and other parameters

Explanation

Solution: In Advanced mode, the Closure Compiler rewrites the JavaScript by renaming variables and functions from longer descriptive names to single letters to save file size, and it inlines functions, coalescing them into single functions wherever it determines that it can.

[#67] The let keyword can be used
Correct Answer

(D) all of the mentioned

Explanation

Solution: The let keyword can be used in four ways : 1. As a variable declaration like var

2. In a for or for/in loop, as a substitute for var

3. As a block statement, to define new variables and explicitly delimit their scope

and 4. To define variables that are scoped to a single expression.

[#68] What is the purpose of the product Minify?
Correct Answer

(C) Proxies the JavaScript file

Explanation

Solution: Minify proxies the JavaScript file
the script tag on the page points to Minify, which is a PHP file.