Answer :
"Acceleration of 5.4 m/s² " means that its speed increases by 5.4 m/s
every second.
If it starts from zero, then after 28 sec its speed is (28 x 5.4) = 151.2 m/s.
every second.
If it starts from zero, then after 28 sec its speed is (28 x 5.4) = 151.2 m/s.