(a)
Taking the angle of the pitch, 37.5°, and the particle's initial velocity, 18.0 ms^-1, we get:
18.0*cos37.5 = v_x = 14.28 ms^-1, the projectile's horizontal component.
(b)
To much the same end do we derive the vertical component:
18.0*sin37.5 = v_y = 10.96 ms^-1
Which we then divide by acceleration, a_y, to derive the time till maximal displacement,
10.96/9.8 = 1.12 s
Finally, doubling this value should yield the particle's total time with r_y > 0
2.24 s
I hope my answer has come to your help. Thank you for posting your question here in Brainly.