Answer:
The equation for regression line and predicting a husband's height for married couples in their early 20s
Equation: Y'=33.67+0.54*X'
Step-by-step explanation:
r=0.5
x'=64.5
Sx=2.5
y'=68.5
Sy=2.7
General regression line equation is:
Y'=a+b*X'
so the slope of the regression line is the linear correlation coefficient multiplied by the standard deviation for y' divided by the standard deviation for x'

The intercept with axis y is the mean of the decreased by the product of the slope and the mean of x

The equation regression line then is:
Y'=33.67+0.54*X'
37 x 10 = 370
21 x 11 = 231
Mark worked 21 Hours, Jack worked 37 Hours.
19. The balloon hits the ground means -16t2+25t+3=0
After you solve the equation, there are 2 solution ~1.67 or ~-0.11 (the time can not be negative) so the solution is 1.67s
20.substitute t=1 to the function -16(1)2+25(1)+3=-16+25+3=12 ft. So the height is 12ft when t=1