Can someone please help if you’re correct I’ll give u brainlist

Julius sold five times as many computers as sam sold last year. in total, they sold 78 computers. how many computers did julius sell?

If the ratio of sum of the first m and n terms of an ap is m2 : n2 , show that the ratio of its mth and nth terms is (2m − 1) : (2n − 1).

What is the value of m in the equation 1/2 m - 3/4n=16 when n=8