Hi, I am a new user and need help please

Consider a certain bacterium that, once in a suitable environment, reproduces with an observed constant doubling time of 2 hours. A 15-milligram mass of the bacteria is present on the initial infection.

d) From this doubling time, calculate the rate at which the bacteria are reproducing per hour.

e) Write the formula for the model to describe the reproduction of the bacteria.

THANK YOU!! Any help is appreciated