1)

<Solve using the formula which is:
Mass=Density×Volume

2)
3)

(Length × Width × Height)


(Answer=7.5)
All the spheres interact with other spheres. For example, rain (hydrosphere) falls from clouds in the atmosphere to the lithosphere and forms streams and rivers that provide drinking water for wildlife and humans as well as water for plant growth (biosphere). ... Flooding rivers wash away soil.
Force exerted by Justin=300 N
Here power= 600 W
distance traveled=10 m
time=5 s
power is given by P= Work done/ time
600=work/5
so work= 60x5=3000J
now work done= force* distance
3000=F *10
F= 3000/10
F=300 N