Need help in under 5 min pls

Bring the fraction a/a-4 to a denominator of 16-a^2

The number of calories you burn depends on your weight. a 110-pound person burns 163 calories during 30 minutes of tennis. find the number of calories that a 190-pound person would burn during the same activity, assuming they burn calories at the same rate.

8litres of paint can cover 129.6 m². how much paint is required to paint an area of 243m²?