Answer: d. 185.4
Step-by-step explanation:
x1 = The time to make the product which is 5 hours
x2 = the number of different materials used which is 4
x3 = the amount spent on marketing the product which is $100
The Regression equation is given as;
y =

Cost = 83 - 2(5) + 0.6(4) + 1.1 (100)
Cost = 83 - 10 + 2.4 + 110
Cost = 185.4