Keith's bank account starts with $250 and he adds $150 to it every month. If m is the number of months that have passed, then the amount of money (in dollars) in his account is given by
250 + 150m
Victoria's account starts with $2000 and she removes half of it each month. So after m months, her account has a value of
2000/2^m
If you were to plot these amounts, then
(a) Keith's account's value is indeed linear - TRUE
(b) Keith is constantly adding money to his account, so its value is increasing - FALSE
(c) Victoria's account's value involves an exponential expression - TRUE
(d) Victoria is removing money, so the value is decreasing - TRUE
Your answers are correct except for (c).