Question: A large national bank charges local companies fir using their services. A bank official reported the results of a regression analysis designed to predict the bank's charges (y), measured in dollars per month, for services rendered to local companies. One independent variable used to predict services charge to a company is the company's sale revenue (x), measured in $ million. Data for 21 companies who use the bank's services were to fit the model

E(y) = β₀+β₁x

Suppose a 95% confidence interval for β₁ is (15, 25). Interpret the interval.

a) We are 95% confident that service charge (y) will decrease between $15 and $25 for every $1 million increase in sales revenue (x).

b) We are 95% confident that the mean services charge will fall between $15 and $25 per month.

c) We are 95% confident that service charge (y) will increase between $15 and $25 for every $1 million increase in sales revenue (x).

d) We are 95% confident that sales revenue (x) will increase between $15 and $25 million for every $1 increase in service charge (y).