i'm not sure how to approach the questions

Write an exponential equation, in the form y = ab* , to model each of the following situations. a. The cost of a home is $350 000 and it increases at a rate of 2.5%/a (per annum). Represent the cost of the home, C(t), after t years. (1 mark) b. A car is valued at $23 000 when it is first purchased, and it depreciates by 12% each year after that. Represent the value of the car, V(n), after n years. (1 mark) c. There are 250 bacteria at the start of a science experiment, and this amount doubles every hour. Represent the total number of bacteria, T(h), after h hours. (1 mark) d. The population of fish in a lake is 5000 and it increases by 7% each year. Represent the population of fish, P(t), after t years. (1 mark)