If an estimator is unbiased, then;
a. the estimator is usually close to the true value.
b. the mean of the estimator is equal to the true value.
c. the mean of the estimator is usually close to the true value.
d. the estimator is equal to the true value.

B

Explanation:

the strict definition of an ubiased estimator says the mean of the estimator is equal to the true value, so if you have the chance to calculate a long number of times, the mean of the estimator in all of those samples will equal to the true value.

it means that an ubiased estimator is specially close to the true value, because in average with a large number of samples, the calculation is made according to the real value

its 2

Explanation:

i took the test and i got this right

answer; buying the bill at a discount from the face value to be received at maturity;