$1200 is invested at 3% compounded quarterly. what is the total amount, to the nearest dollar, after 5 years?

How do you solve a question like this?

If 1/√5+1/√5+1=p+q√r , find the values of p, q and r

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 (%)