I need help with these homework questions.

Question 32. What amount must be deposited today at an interest rate of .9% per year compounded continuously to have a future amount worth $7000 in 15 years?

Question 36. Suppose you want a future income stream of FV(t) = 30,000 + 1000t for 20 years starting today. Find the present value PV of the income stream, assuming an interest rate of 4% per year compounded continuously.

Question 56. Natural Gas The rate at which natural gas was consumed ( in billions of cubic feet per year) by the industrial sector for lease and plant fuel can be approximated by

f(x) = 3x - 14x + 1131 (0 5 x s IS)