Find the intrest on 40,000 form2 yrs at 20%nper annum compound intrest

If the public debt of a country in 2009 was $10432000000000 and the budget for 2010 was in deficit by $201645000000, what was the public debt in 2010? do not include commas in your answer.

How do i do this activity, is appreciated

Car a and car b were in a race .the driver of car b claimed that his car was twice as fast as car a