(a)[2]
Determine $r$ when $n = 180$ and $c = 3$.
(b)[2]
Factorise $20p^2q - 5p$ fully.
(c)[2]
Write down an expression that gives the total cost, in cents, of $x$ apples and $y$ bananas.
(d)[4]
Solve the simultaneous equations, showing all your working.