Q: An experiment was conducted to study the effect of increasing the dosage of a certain barbiturate on sleeping time. Three readings were made at each of three dose levels.

Sleeping Time (Hours) (Y) 4 6 5 9 8 7 13 11 9

Dosage (M/kg) (X) 3 3 3 10 10 10 15 15 15

1- Plot the scatter diagram.

2- Determine the regression line relating dosage (X) to sleeping time (Y).

3- Test the hypothesis of no linear relationship between variables.

a. What is the predicted sleeping time for a dose of (12 M/kg)?​