The milligrams of ibuprofen in an adult's body is given by the equation a = 400 • (3/4) ^t where t is the number of hours since the adult took the ibuprofen.

1. how much ibuprofen will be in the adults body after 2 hours ( show work )

2. in the equation, what does 400 tell us about the situation
( write description, use full sentence)

3. in the equation what does the 3/4 tell us about the situation ( write description, use full sentence)