Please need help on this math

If a baseball player hits a baseball from 4 feet off the ground with an initial velocity of 64 feet per second, how long will it take the baseball to hit the ground? use the equation h = −16t2 + 64t + 4.

Billie holiday sells children's clothing for sara vaughn's toddler shop. baby blankets sell for $29.99 after a markup rate based on cost of 109%. find the cost and the markup.

The least common denominator of 4/8 and 11/18