A muon with rest energy $106 \mathrm{MeV}$ is created at an altitude of $4500 \mathrm{~m}$ and travels downward toward Earth's surface. An observer on Earth measures its speed as $0.980 c$. (a) What is the muon's total energy in the Earth observer's frame of reference? (b) What is the muon's total energy in the muon's frame of reference?