Write Each Rational Expression in Lowest Terms, and Give the Domain

Essay

Write each rational expression in lowest terms, and give the domain.
(a) $\frac{12 y^{5}}{4 y^{13}}$
(b) $\frac{2-t}{4-t^{2}}$
(c) $\frac{x^{2}+5 x+6}{x^{2}-2 x-15}$