What type of material arrangement was most common in the kichai tribe?

Which expression is equivalent to the expression below? (6c^2 + 3c) / (-4c + 2) / (2c + 1) / (4c - 1)a. 3c(2c-1) / (2c + 1)b. -3c(2c-1)^2 / (2c + 1)^2c. 3cd. -3c(just took the test its d. -3c)

Can someone explain to me how to do

Assume that y varies inversely with x. if y=1.6 when x=0.5 find x when y=3.2