Because no sunlight can penetrate it
There are not enough electrons in atoms to affect the total mass, so the total mass is just the weight of the protons and neutrons.
Use conservation of momentum.
Initial momentum = 0
Final momentum = momentum of the girl + momentum of the boy = inifial momentum = 0.
Momentum of the girl = - momentum of the boy
mass of the girl * velocity of the girl = - mass of the boy * velocity of the boy
50 kg * velocity of the girl = - 80 kg * 3m/s
=> velocity of the girls = -80 kg * 3m/s / 50 kg = - 4.8 m/s
Answer: - 4.8 m/s
B. <span>so the oven is warm when the dough is ready to bake
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