The dimensions of rectangle B are twice the dimensions of rectangle A. The area of rectangle A is 128 cm2.

What is the area of rectangle B?

Let the length and width of rectangle A be L and W, respectively.

Therefore, the area of rectangle A is given by: A = L*W = 128

Let the length and width of rectangle B be 2L and 2W, respectively.

Therefore, the area of rectangle B is given by: A' = (2L)*(2W) = 4*(L*W) = 4*(A) = 4*128 = 512 cm^2

So, the area of rectangle B is 512 cm^2.