$3.$ If your task is to crash this project by $2$ days, what is the most efficient cost of doing it$?($Just input the number with no decimals or dollar signs$)$

$4.$ Suppose that the project duration that you have calculated in question $2($before crashing$)$ is the expected duration of the project. Its variance of the critical path is $4$ days. The principal requires you to complete the project before the day $15.$ If you finish later, you will incur a fine

What is the probability of receiving a fine?

$5.$ Your manager wonders whether or not you should crash the project by $2$ days. If you do$,$ the variance of the project duration will remain the same. What is the probability that you will receive a fine? Based on your calculations in Q$4$ and Q$5,$ would you recommend crashing the project?