please post all work. thank you

The time (in days) for each activity is written below each activity, in the drawing below. You gain $1,200 in revenue for every day faster you can complete the project. In the text box, please answer the following: 1. To maximize profits, which activities should be crashed, and how much? Show me as much information as you would like to in the text box, so I can see how you got to your answer. (8 points) 2. If we do the optimal amount of crashing, how long will the project take to complete? ( 4 points) 3. How much additional profit do you make from the crashing? ( 3 points)