If the result of increasing a by 300% of a is b, then a is what percent of b?

If a % of a + b% of b = 2% of ab, then what percent of a is b?

If a number is increased by 20% and the resulting number is again increased by 20%, then what per cent is the total increase?

If the radius of a sphere is increased by 50%, find the increase percent in volume and the increase percent in the surface area.