#### Flaming Toilet

Ok, I drew a force diagram with F (tension; upward direction)on the string and mg (weight) going down. Then, I found acceleration using the Vf-Vi divided by time : a=(Vf-Vi)/t

a=(20.0 m/s - 0 m/s)/5.0 s

a= 4.0 m/s squared

However, I have no idea what to do next. Can anyone give a hint(s) on what to do next?