Answer & Solution
Answer: Option A
Solution:
The isNaN function determines if a value is NaN (Not-a-Number).
Q
What does the isNaN function do?
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A). typeof variable === 'array'
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A). 1
B). 0
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A). Converts a number to a string
B). Converts a string to an integer
C). Converts a boolean to a number
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A). number
B). NaN
C). undefined
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A). string
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C). undefined
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A). array
B). object
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A). 30
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A). null
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