A least squares regression line a. can be used to predict a value of y if the corresponding x value is given. b. implies a cause-and-effect relationship between x and y. c. can only be determined if a good linear relationship exists between x and y. d. ensures that the predictions of y outside the range of the values of x are valid.

The correct option is (a).

Step-by-step explanation:

The general least square regression line is given by,

Here,

X = independent variable

Y = dependent variable.

b = slope (or regression) coefficient

a = intercept

The main purpose of the least square regression line is to predict the value of the dependent variable when the independent variable is known.

So, the correct interpretation is:

A least squares regression line can be used to predict a value of y if the corresponding x value is given.

The correct option is (a).

tip $2.90

total $17.40

one fourth of 9% = 2.25%

gavin is correct in saying : the equivalent quarterly interest rate would be

2.25%.