First post so bear with me if they dont come out right :-)

Im not too sure about the working, i have done this just now and came up with 30.375, the steps i have taken are a bit confusing though.

Thanks very much to anyone who gives me a hand.

1. Calculate at t=4

2. Calculate when t= 0.01sec

for this i ended up with 3.1354

I have a few others but any help with these would be greatly appreciated