Regression analysis was applied between sales data (in $1,000s) and advertising data (in $100s) and the following information was obtained.

~
y = 12 + 1.8x

n = 17
SSR = 225
SSE = 75
sb1 = 0.2683


Refer to Exhibit 12-3. The critical F value at a = 0.05 is

a. 3.59

b. 3.68

c. 4.45

d. 4.54