Dandy manufacturing company usefs two different independent variables (machine-hours and number of pachages) in two different equations to evaluate costs of the packaging department. The most recent results of the two regressions ar e as follows: Machine hours:
Variable Cofficient Standard error t-value
Constant $748.30 $341.20 2.19
Independatn variable $52.9 $35.20 1.50

r^2=0.33

Number of packages:
Variable Cofficient Standard error t-value
Constant $242.90 $75.04 3.24
Independatn variable $5.60 $2.0 2.80

r^2=0.33

Required:
a. What are the estimating equations for each cost driver?
b. Which cost driver is best and why?