Seasonality can be forecast using a multiplicative model to create a seasonal index.

While they are loosely equal (undefined == null is true), they are not strictly equal. Strict equality (===) checks for both value and type, and undefined and null are two distinct primitive types.

Option 2 (Mathematics):

True or False: In mathematics, the result of dividing a number by zero is undefined.

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Answer: True.

Division by zero is an operation for which there is no meaningful result defined within the set of real numbers. For example, in the equation x = 5 / 0, there is no number x that, when multiplied by 0, would equal 5.

Option 3 (General Programming):

True or False: A variable that has been declared but has not yet been assigned a value is considered "null".

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Answer: False.

In many languages (most notably JavaScript), a variable that has been declared but not assigned a value is undefined. Null is typically an intentional assignment representing "no value" or "no object," whereas undefined means a value has not been assigned yet.