Let d(t) denote the depth, in meters, of the water at a fixed location of a bay t hours from noon. Find a formula for each function below by applying transformation(s) to d(t).

a) f(t)=d(t)+5
b) g(t)=2d(t)
c) h(t)=−d(t)
d) k(t)=d(t−3)