To determine horizontal component of velocity
as we know
R = u2sin2θ/g -----1
T = 2usinθ/g -----2
now expanding the equation for range R , we get R = 2u2sinθcosθ/g ----3
dividing equation 3 by equation 2
we get [2u2sinθcosθ/g]/[ 2usinθ/g] = R/T
thus we have
ucosθ = R/T
or ucosθ = 200/5 = 40m/s
as we know ucosθ is the horizontal component of velocity when θ is the angle with the horizontal.