Answer:
Force = mass × acceleration
Acceleration:
[tex]{ \tt{15 = (22 \times a)}} \\ { \tt{a = \frac{15}{22} \: {ms}^{ - 2} }}[/tex]
From first Newton's equation of motion:
[tex]{ \bf{v = u + at}} [/tex]
Change = v - u:
[tex]{ \tt{v - u = (a \times t)}} \\ { \tt{v - u = ( \frac{15}{22} \times 1.2) }} \\ { \tt{v - u = 0.82 \: {ms}^{ - 2} }}[/tex]