True will end up being the answer
Answer:
All answers attached in the pictures above.
KE=3070.625 J
Height = 3.686 m
<h3>Further explanation</h3>
mass of bike+rider=85 kg
velocity = 8.5 m/s

Conservation of energy :
(KE+PE)₁ (downhill) = (KE+PE)₂ (up the hill)
PE₁=0⇒h=0
KE₂=0⇒v=0(stop), so equation becomes :
KE₁=PE₂

In one mole of talc, we observe that there are:
3 moles of Mg
4 moles of Si
2 moles of H
12 moles of O
The molar ratio of O to Mg is then:
12 moles of O : 3 moles of Mg = 4 : 1
Therefore, if 6.1 moles of Mg are present, the moles of O are:
4 * 6.1 = 24.4 moles of O