Point out the correct declaration of the height variable:, variable height;, let height;, height is variable;, height;, Review the code: let age = 32; age = age + 1; console.log(Age); Result?, 33, 32, Error: Age not defined, undefined, If a variable stores false, it is:, Math type, Unused, Logical type, Boolean type, Analyze the code: let x = 10 / 100; console.log(typeof(x)); Result?, number, 0.1, Error: Fractional ops, fraction, Operation: let x = 100 / 0; Result?, NaN, Infinity, 0, Undefined, Operation: let x = 20n + 10; Result?, 30n, 30, "20n10", Error, To get string length from msg:, msg.chars, msg.length, msg.length(), msg.charsAt(), Operation: let x = "abcdef".slice(2, 4); Result?, "cdefg", "ab", "cd", "cdef", Change dog age to 6:, dog.age = 6;, dog[age] = 6;, dog(age) = 6;, dog.age = 5;, Change "July" to 7 in array:, Not possible, summer[1] = 7;, summer.July = 7;, summer[0] = 7;.

JavaScript Basics Quiz

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