As the body is stationary then the initial velocity u=0.

Now from kinematics we know, Displacement (S) = ut+0.5at^2

As u=0 then S=0.5at^2 -----------(i)

Now its given S=10m , t=4s ., substituting in equation (i) we get,

10 = 0.5*a*4^2 => a = 10*2/16 = 5/4 m/s^2

Thus we get the acceleration to be 5/4 m/s^2.

Now we know from the Equation of Motion : Force (F) = mass(m)*acceleration(a)

Thus the required Force, F = 2kg * 5/4 m/s^2 = 2.5 kgm/s^2=2.5N

I hope this answer helps. All the very best for your future endeavors!