I am soooooo confused with this one. Don't even know where to start... Any help would be appreciated!!!

On November 1st, 10 people at your school had the flu virus. The number of people infected by the virus is doubling every day.

a) Write a function, N(t), where N is the number of people infected and t is the time, in days, since November 1st. Use the function to determine the number of people infected after 4 days.

b) Determine the average rate of change for N(t) between November 3rd and November 4th.

c) If there are 1525 people at your school, approximately how many days will it take until everyone is infected with the virus? (Round to 1 decimal place.)