The book's vertical position in the air is

where
. It reaches the ground when
, at a time
such that

So it takes the book 4 seconds to reach the bottom. The given initial velocity is irrelevant since it only has a horizontal component; vertically, the book is starting from rest.
Answer:
He is wrong!
Explanation:
Frequency refers to how many wave lengths pass in a second and speed is how fast the wave is traveling for example the speed of light goes really fast but has a mid-level frequency.
Hope this helps! ;-)
Since 0 C and 32 F are temperatures when water freezes, anything lower then that would be colder and since 20 F is less than 32 F,
20 F is colder than 0C