B is the answer
10x7= 70 (Base 1)
10x7= 70 (Base 2)
10x4= 40 (Front)
10x4= 40 (Back)
7x4= 28 (Side 1)
7x4= 28 (Side 2)
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SA= 276
Remember to think of a rectangular prism as a box, then label the base, the width, and the height :)