for first question
there are four engines .. each producing 250,000 N so total comes 4*250,000 N
is has weight 400,000 kg
thus Calculate it 4*250,000/400,000 gives you the answer
2nd question
after calculating acceleration from first part
apply it to the third equation of kinematics
v^2 = u^2 + 2asS.
where s is the distance required
