Answer:
The engine should be turned off at t = 1
Step-by-step explanation:
The detailed and step by step calculation is shown in the attachment below
345500=pmt[(1-(1+0.04875/12)^(-12×15))/(0.04875/12)]
Solve for pmt
Pmt=2709.75
Y = 3/5x + b
3 = 3/5(-1) + b
3 = -3/5 + b, b = 3 3/5
Y = 3/5x + 3 3/5