This is ur answer for Q1
1.Uranium is scarcer, more difficult to mine and must be refined. It requires a fairly complex reactor. Coal is common, easy to mine and can be burned as-is. Coal-fired generators are lower-tech and much dirtier.
In terms of energy density, reactor-grade uranium is over 10,000 times more energy-dense than coal. If used in a fast breeder reactor (the kind used to make plutonium), over a million times more energy can be extracted.
Consequently, the amount of energy used shipping fuel to the power plant is a great deal less for uranium, and uranium plants can work for a long time between fuel shipments.
The extremely high density of the fuel is why nuclear reactors power America's large warships and submarines. They can stay at sea without frequent refueling. It's also needed for deep-space missions, where there is no oxidizer to make a chemical fuel work.
Over its lifetime, a nuclear plant probably produces less environmental damage and poses less of a risk to public health than a coal-fired plant. It's pollutants, while highly dangerous, are well contained and small in volume.
Nuclear reactors are comparatively slow to cool down, so they're not optimal for dealing with a load that peaks and dips sharply. Gas is better for that.