I need help ASAP plz

I need help with engineering economic assignment its due in 12 hrs. the answers should be step by step and you have to show all of ur work plz.

These are the Qs;-

1.    You plan to deposit an amount into a savings account that pays 5.5% annual interest.   How many years you have to wait until your money doubles?

2.    You have a $3,000 and consider putting it in a savings account that pays 2.75% annual interest rate.  How much money there will be in your account 5 years later?

3.    You want to have $3,000 in your account 5 years later. How much money you need to put into account now? Account pays an inetredt of 2.5% annually.

4.    A used casr parking lot has the following deal on a $18,000 car. Zero down and $385 minthly payements for 60 months.  What is the monthly rate they charge?

NOTE: DRAW ALL CASH FLOW DIAGRAMS