normal standard deviation

Suppose that we are told that the weights of 5-year old children in a

particular region of the world are normally distributed with a mean of 16 KGs and

standard deviation of 5 KGs.

a. Approximately what proportion of 5-year old children are heavier than 20 KGs?

b.What proportion of 5-year old children are between 20 and 22 KGs?

c. What weight corresponds to the point where 20% of all 5-year old children are greater than this weight?