According to question, u = 49 m/s

at the maximum height

v = 0, g = 9.8 m/s²

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(i) From the equation

v² = u² – 2gh

0 = (49)² - 2 x 9.8 x h

19.6h = 49 x 49

h = (49 x 49) / 19.6

h = 122.5 m

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(ii) While throwing upward

v = u - gt

t = (u-v)/(-g)

t = -49/-9.8

t = 5s

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∵ The ball takes the same time to reach the surface from the maximum height

∴ total time = (5 + 5)s = 10s