Could someone check these for me? i was told to put g = 9.8 m/s for all calculus questions, and I think it's a bit ridiculous.

1. A long jumper running at 8 m/s jumps into the air, rising to a height of 0.7 metres. What is the length of the jump.

maximum height

Range

This is wrong. the answer says 5.29 m.

2. The velocity of a point moving along the x axis is given by

Show that it is simple harmonic.

However this is not the form

so how would I do this?

Thanks!!! You guys are really helpful!