Answer:
U = 2,195 10⁵ J
Step-by-step explanation:
The potential energy is
U = m g and
in this case each person has a mass of 75 kg and the elevator has a mass of 500 kg, the total mass is
m_total = m_elevator + 4 m_person
m_total = 500 + 4 75
m_toal = 800 kg
let's calculate
U = 800 9.8 28
U = 2,195 10⁵ J