Answer:
[tex]{ \bf{average \: velocity = \frac{15 + 40}{2}}} \\ = 27.5 \: {ms}^{ - 1} \\ { \bf{acceleration = \frac{v - u}{t} }} \\ = \frac{40 - 15}{10} \\ = 2.5 \: {ms}^{ - 2} \\ \\ { \tt{second \: qn : }} \\ { \bf{final \: velocity =u + at }} \\ v = 0 + (5 \times 10) \\ = 50 \: {ms}^{ - 1} [/tex]