To formulate the linear model, we first need to find out the crash costs per week. This is calculate

To formulate the linear model, we first need to find out the crash costs per week. This is calculated using the formula (Crash cost – Normal Cost) / (Normal time – Crash time). This is calculated for each of the activities as shown belowThe variables that considered for are belowLet xi (i = 1 to 8) be the earliest start time of each activity andyi (i = 1 to 8) be the crash times for each activity. xs and xf are the start and finish time.The objective function is to minimize the total crash cost. This can be represented asMinimize : 6y1 + 12y2 + 4y3 + 6.67y4 + 10y5 + 7.3y6 + 5.75y7 + 8y8subject to constraintsy1 = 5×2 – xs + y2 >= 3×3 – x1 + y3 >= 4×4 – x1 + y4 >= 6×5 – x2 + y5 >= 5×6 – x2 + y6 >= 7×7 – x3 + y7 >= 9×7 – x5 + y7 >= 9×8 – x4 + y8 >= 9×8 – x6 + y8 >= 8