What is the quotient? 2y^2-6y-20/4y+12 / y^2+5y+6/3y^2+18y+27
a) 2/3(y-5)
b) 3(y-5)/2
c) (y-5)(y+2)^2/6(y+3)^2
d) 3(y+5)(y-2)/2(y+2)

Do one of the following, as appropriate: (a) find the critical value z subscript alpha divided by 2 , (b) find the critical value t subscript alpha divided by 2 . 99%; nequals 17; sigma is unknown; population appears to be normally distributed.