OK so basically when converting 2 meters per second to kilometers per hour you will get 7.2 kilometers per hour. OK so times that by 4 and you will get 28.8 kilometers in 4 hours.
B and C (I think they are the same)
I hope this helps you
2.5.7+2.5.12+2.7.12
70+120+168
358
A = (B + b)xH : 2
A = (4.5+7.5) x 5 : 2
A = 12 x 5 : 2
A = 60 : 2
A = 30 in²