physics. in need of help. anyone want to help?

Question

1a. A dragster and driver together have mass
930.6 kg. The dragster, starting from rest,
attains a speed of 26 m/s in 0.61 s .
Find the average acceleration of the drag-
ster during this time interval. Answer in units
of m/s2.
1b. What is the size of the average force on the
dragster during this time interval? Answer in
units of N.
1c. Assume: The driver has a mass of 71.5 kg :
What horizontal force does the seat exert
on the driver? Answer in units of N.

Answer 1

1a
a=V/t=26/0.61=42.6m/s^2

1b
F=ma= 930.6 x 42.6= 39700 N

1c. F=ma=71.5 x 42.6=3050 N

Answer 2

Acceleration a = [v - u ] / t
u = 0; a = 26 / 0.61 = 42.62 m/s^2.
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Force = mass x acceleration
F = 930.6 x 42.62 = 39665 N
-------------------------------------
F = mass x acceleration
F = 71.5 x 42.62 = 3047.33 N