D. because the size and shape of the slope determines weather the load can be sustained and c is correct too because the shape affects how much you can load and b. is correct as also because if the volume is very large it can affect the rivers load and flow.
81. There is 1 carbon, 2 chlorine and fluorine atoms in Freon 12. To draw them it forms a cross with C in the middle and Cl and F both on the opposite side.
