What is the length of QS?

In triangle opq right angled at p op=7cm,oq-pq=1 determine the values of sinq and cosq

The table shows the balance of a money market account over time. write a function that represents the balance y (in dollars) after t years.

Given the two similar triangles, how do i find the missing length? if a=4, b=5, and b'=7.5 find a'