Pleas help with this ah im dying

Use set builder notation to represent the following set: { -3, -2, -1, 0}

Write 5(6x+4)-2(5x-2) in the form a(bx+c) where a,b and c integers and a> 1

21 a stick 7 inches long is broken into two pieces, so that one piece is twice as long as the other one. how long are the two pieces?