Question

a body travels 200 CM in the first 2 seconds and 220 CM in the next 5 second calculate the velocity at the end of the 7th second from the start

Answer 1

velocity = Displacement /total time .
v=(200+220)/(2+5)
v=420/7
v=60cm/s

Hope you like the answer.

Answer 2

$\textbf{Answer is in Attachment !}$