Plz do this all plz ​

What are the relative frequencies to the nearest hundredth of the columns of the two-way table? a b group 1 102 34 group 2 18 14

What is the size of the matrix resulting from

1) prove that 731^3−631^3 is divisible by 100 2) prove that 99^3−74^3 is divisible by 25