please help me do (i) and (ii) (using VBA)

Homework 1 Derive the closed-form formula for an option with the following payoff function: Payoff at T K-K ST 0 K KA Basic requirement (80 points): (i) Utilize the martingale pricing method to derive the closed-form formula by hands. (ii) Based on the formula you derive, implement a program to price this option. (Inputs: So, r, q, 0, T, K1, K2, K3, K4. Output: Option value.) Homework 1 Derive the closed-form formula for an option with the following payoff function: Payoff at T K-K ST 0 K KA Basic requirement (80 points): (i) Utilize the martingale pricing method to derive the closed-form formula by hands. (ii) Based on the formula you derive, implement a program to price this option. (Inputs: So, r, q, 0, T, K1, K2, K3, K4. Output: Option value.)