a) Corresponding angles of similar figures are congruent, so [tex]\angle B \cong \boxed{\angle Z}[/tex]
b) Scale factor = (image)/(preimage). Since we are looking for ABCD to WZYX, this means that WZYX is the image and ABCD is the preimage. Thus, the scale factor is [tex]\frac{25}{10}=\boxed{5/2}[/tex]
c) Since the scale factor is 5/2,
[tex]\frac{20}{t}=\frac{5}[2}\\\\40=5t\\ \\ t=\boxed{8}[/tex]
