Elevator going down and you drop a book

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kmiller
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Homework Statement



While riding on an elevator descending with a constant speed of 3.3 m/s, you accidentally drop a book from under your arm.
(a) How long does it take for the book to reach the elevator floor, 1.1 m below your arm?
s
(b) What is the book's speed (relative to the earth) when it hits the elevator floor?


The Attempt at a Solution



4.9m/9.8m/s2=14.7
squareroot 14.7=3.834=answer a

1.1m+1/2(13.1)t
t=7.65
1.1m/7.65s=.1437=answer b

both of these answers were wrong. what equations am ia supposed to use?
how do i start?
 
on Phys.org
For the first part it looks as though you're trying to use the correct equation but I have no idea where you got your numbers from?

For part b it will just be the speed of the elevator added to the speed you work out from standard kinematic equations.