What is the value expression I -2 - (-2.5) I

What is the exact volume of the cylinder? 16in going into the middle of the top of the cylinder and 40in in height a) 25,600(pi)3 b)10,240(pi)3 c)1280(pi)3 d)640(pi)3

Rhombus adef is inscribed into a triangle abc so that they share angle a and the vertex e lies on the side bc . what is the length of the side of the rhombus if ab=c, and ac=b.

Which property was used to simplify the expression? 3c+9 +4c=3c+4c+9