The forecast error is the difference between a. the actual value and fitted value b. the forecast value and fitted value c. the independent variable value and the dependent variable value d. this period’s value and the next period’s value

Option a is right.

Step-by-step explanation:

When we do forecasting i.e. estimating before it really happens we come across the situations where actual will slightly deviate from the forecast value.

This difference i.e. actual or real value - predicted value is called the forecast error.

Here hence option a is right.

Option b is wrong because we subtract only fitted value from real value

Option C is wrong because the independent and dependent variable has nothing to do with forecast error.

D is wrong because the period difference is not forecast error

here you hope this .

step-by-step explanation:

hypotenuse = √(15² + 8²)

=  √(225 +64)

=  √(289) = 17

sin(x) = cos(y) = 8/17

they are identical so long as you are doing the sine of one angle and the cosine of the only other angle that isn't the right angle.