Ive Worked Out How To Get Rich Quick !!!PROBLEM!!!

"Ive worked out how to get rich quick" said nadia. "lets send emails telling people to send us $1 and to send copies of the email to four friends. in return we will offer them seven years good luck. if everyone responds and the chain grws a link a week, we will collect $4 in week 1, another $16 dollars in week 2. we will be millionaires in less than three months!" how long would it take to collect one million dolars?

HELP ME IM IN GRADE 8 AND I CANT FIGUIRE IT OUT ITS DOING MY HEAD IN ANY HELP WOULD BE GREATLY APPRECIATED.(Doh) ITS DUE IN TWO DAYS PLEASE HELP!