Please help me solve the ff:

The employees of a subsidiary that does asbestos cleanup are being tested for indications of asbestos in their lungs. The rm is asked to send four employees who have positive indications of asbestos on to a medical center for further testing. Suppose 40% of the employees have asbestos in their lungs. Let Xi be the number of employees who are screentested to nd one who has positive indications of asbestos in his/her lungs. a. Let Y be the total number of employees tested to nd four with positive asbestos in their lungs. Dene Y as a function of X. Using the MGF technique, nd the probability distribution of Y. b. Concerned with the cost of screening test, Lee Hu Kay would like to know the maximum number of employees tested to nd one who has positive indications of asbestos in hisfher lungs (Z). Given X1, X2, X3 and X4, derive the distribution function of Z. 0. Suppose the cost of each screening test is 5000 pesos. Let W be the total cost incurred by the company to find one employee who has positive indications of asbestos in his/her lungs. Find the distribution function of W using the CDF technique