Do these for me please i really need help

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 (%)

Someone me what is the area of this figure? 18m 18m 8m 16m

What is the point slope form of a line with slope -5 that contains point (2,-1)