A statistic is said to be unbiased if

a. the mean of its sampling distribution is equal to the true value of the parameter being estimated.
b. it is used for only honest purposes.
c. the person computing it doesn't favor any particular outcome.
d. the person who calculated the statistic and the subjects whose responses make up the statistic were truthful.

A statistic is said to be unbiased if the mean of its sampling distribution is equal to the true value of the parameter being estimated.

Step-by-step explanation:

A parameter is a number that describes the population.  

A statistic is a number that describes a sample.  

A statistic used to estimate a parameter is unbiased if the mean of its sampling distribution is exactly equal to the true value of the parameter being estimated. For example, the mean of a sample is an unbiased estimate of the mean of the population from which the sample was drawn.

A statistic is biased if its expected value is not equal to the parameter.

which expression represents the approximate length of bc?

step-by-step explanation:

hope this !

let me know