The average particle density in the milky way galaxy is about one particle per cubic centimeter. express this number in si units kg/m^3. assume that the universe is made up of 70% hydrogen and 30% helium. be very detailed with how you come up with the numbers..

In which of the following cases is work being done on an object? question 2 options: pulling a trailer up a hill carrying a box down a corridor suspending a heavy weight with a strong chain pushing against a locked door

Atank has a shape of a cone with a radius at the top of 2 m and a height of 5 m. the tank also has a 1 m spout at the top of the tank. the tank is filled with water up to a height of 2 m. find the work needed to pump all the water out the top of the spout. (use 9.8 m/s2 for g and the fact that the density of water is 1000 kg/m3.)

Which change would make the diagram correct?