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Q. Consider the following code snippet :
var grand_Total=eval("10*10+5");
The output for the above statement would be :

(A) 10*10+5
(B) 105 as a string
(C) 105 as an integer value
(D) Exception is thrown

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Q. Consider the code snippet given below
var count = [1,,3];
What is the observation made?

(A) The omitted value takes “undefined”
(B) This results in an error
(C) This results in an exception
(D) None of the mentioned

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Q. Consider the following code snippet
var a1 = [,,,];
var a2 = new Array(3);
0 in a1
0 in a2
The result would be

(A) true false
(B) false true
(C) true true
(D) false true

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Q. The pop() method of the array does which of the following task ?

(A) decrements the total length by 1
(B) increments the total length by 1
(C) prints the first element but no effect on the length
(D) None of the mentioned

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Q. Consider the following code snippet :
if (!a[i]) continue ;
What is the observation made ?

(A) Skips the undefined elements
(B) Skips the non existent elements
(C) Skips the null elements
(D) All of the mentioned

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Q. What will happen if reverse() and join() methods are used simultaneously ?

(A) Reverses and stores in the same array
(B) Reverses and concatenates the elements of the array
(C) Reverses
(D) All of the mentioned

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Q. Consider the following code snippet :
var a = [1,2,3,4,5];
a.slice(0,3);
What is the possible output for the above code snippet ?

(A) Returns [1,2,3]
(B) Returns [4,5]
(C) Returns [1,2,3,4]
(D) Returns [1,2,3,4,5]

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Q. Consider the following code snippet :
var a = [];
a.unshift(1);
a.unshift(22);
a.shift();
a.unshift(3,[4,5]);
a.shift();
a.shift();
a.shift();
The final output for the shift() is

(A) 1
(B) [4,5]
(C) [3,4,5]
(D) Exception is thrown

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Q. The primary purpose of the array map() function is that it

(A) maps the elements of another array into itself
(B) passes each element of the array and returns the necessary mapped elements
(C) passes each element of the array on which it is invoked to the function you specify, and returns an array containing the values returned by that function
(D) None of the mentioned

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Q. The reduce and reduceRight methods follow a common operation called

(A) filter and fold
(B) inject and fold
(C) finger and fold
(D) fold

JavaScript MCQs with answers Page - 67

Q. Consider the following code snippet :
var grand_Total=eval("10*10+5");
The output for the above statement would be :

Q. Consider the code snippet given below
var count = [1,,3];
What is the observation made?

Q. Consider the following code snippet
var a1 = [,,,];
var a2 = new Array(3);
0 in a1
0 in a2
The result would be

Q. The pop() method of the array does which of the following task ?

Q. Consider the following code snippet :
if (!a[i]) continue ;
What is the observation made ?

Q. What will happen if reverse() and join() methods are used simultaneously ?

Q. Consider the following code snippet :
var a = [1,2,3,4,5];
a.slice(0,3);
What is the possible output for the above code snippet ?

Q. Consider the following code snippet :
var a = [];
a.unshift(1);
a.unshift(22);
a.shift();
a.unshift(3,[4,5]);
a.shift();
a.shift();
a.shift();
The final output for the shift() is

Q. The primary purpose of the array map() function is that it

Q. The reduce and reduceRight methods follow a common operation called

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JavaScript MCQs with answers Page - 67

Q. Consider the following code snippet : var grand_Total=eval("10*10+5"); The output for the above statement would be :

Q. Consider the code snippet given below var count = [1,,3]; What is the observation made?

Q. Consider the following code snippet var a1 = [,,,]; var a2 = new Array(3); 0 in a1 0 in a2 The result would be

Q. The pop() method of the array does which of the following task ?

Q. Consider the following code snippet : if (!a[i]) continue ; What is the observation made ?

Q. What will happen if reverse() and join() methods are used simultaneously ?

Q. Consider the following code snippet : var a = [1,2,3,4,5]; a.slice(0,3); What is the possible output for the above code snippet ?

Q. Consider the following code snippet : var a = []; a.unshift(1); a.unshift(22); a.shift(); a.unshift(3,[4,5]); a.shift(); a.shift(); a.shift(); The final output for the shift() is

Q. The primary purpose of the array map() function is that it

Q. The reduce and reduceRight methods follow a common operation called

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Q. Consider the following code snippet :
var grand_Total=eval("10*10+5");
The output for the above statement would be :

Q. Consider the code snippet given below
var count = [1,,3];
What is the observation made?

Q. Consider the following code snippet
var a1 = [,,,];
var a2 = new Array(3);
0 in a1
0 in a2
The result would be

Q. Consider the following code snippet :
if (!a[i]) continue ;
What is the observation made ?

Q. Consider the following code snippet :
var a = [1,2,3,4,5];
a.slice(0,3);
What is the possible output for the above code snippet ?

Q. Consider the following code snippet :
var a = [];
a.unshift(1);
a.unshift(22);
a.shift();
a.unshift(3,[4,5]);
a.shift();
a.shift();
a.shift();
The final output for the shift() is