An object is thrown upward from the top of an 80ft tower.
the height h of the object after t seconds is represented by the quadratic equation h= -16t^2 + 64t + 80.

after how many seconds will the object hit the ground?

a. 29 seconds
b. 6.4 seconds
c. 5.0 seconds
d. 8.0 seconds

she played for 18.75 hours.

step-by-step explanation:

if she played 2/4 of a hour on tuesday. and there is 60 minutes in an hour and 60 divided by 4 is 7.5. and she played 2/4 of an hour on thursday then again 60 divided by 4 is 7.5, you add 7.5+7.5=56.25. now you have to do 1/4 of an hour, it equals 3.75. now you have to add them all up. 3.75+7.5+7.5=18.75

i hope this and i hope you get it right. it took me a while to get this done for you. : )