The answer's are on the image sorry if you can see it

Iam so stuck. what is the worked out answer for this question?

If eh = hg and hg=16, find the diameter of k

Acompany that manufactures and sells guitars made changes in their product range. from the start they had 20 models. then they reduced the number of models to 15. as a result, the company enjoyed a 10% increase in turnover. - how much did the stock level change? in (%)