Answer:
(a) 27.1 m/s
(b) 3.9 second
Explanation:
Let the speed is u.
Maximum horizontal range, R = 75 m
The range is maximum when the angle of projection is 45°.
(a) Use the formula for the maximum horizontal range
[tex]R=\frac{u^{2}}{g}[/tex]
[tex]75=\frac{u^{2}}{9.8}[/tex]
u = 27.1 m/s
(b) Let the time of flight is T.
Use the formula for the time of flight
[tex]T=\frac{2uSin\theta}{g}[/tex]
[tex]T=\frac{2\times 27.1 \times Sin45}{9.8}[/tex]
T = 3.9 second
