need some help with this

Engr. Secular became a full professor when he was hired in a State university at the age of 34. Assuming that there is no salary increase, it is estimated that he will pay a total of P5,294,225.88 for his mandatory contribution to the Government Service Insurance System (GSIS) until his retirement at the age of 65. a) How much is his monthly salary, if the mandatory deduction in his monthly salary is only 9% for his GSIS contribution? Write your answer below, and show the complete solution in your solution sheet. [5 points] b) Determine the future equivalent worth of his contributions when he retire if the government interest rate is maintained at 8%. Write your answer below, then show the Cash Flow diagram (with functional symbols) and complete solution in your solution sheet. [5 points] c) If he lives 35 more years after retiring, what annual withdrawal can he expect from his contribution? Write your answer below, and show the complete