To find how long it takes for the object to hit the ground you need to set h(t)=0 after this you need to find the number that when plugged into t makes the equation equal to 0
I may be wrong but if each of the four rooms required two cans, 4x2 is 8. then it says you spilt half a can, making that 8.5 cans. but, you have 1.5 cans left. 8.5+1.5= 10.
