Helena is an engineer that designs packaging for new products. She designed a box in the shape of a rectangular prism with dimensions of 10 inches by 7 inches by 4 inches. What is the surface area of the box?

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Find the greatest common factor of the followig monomials 21u^5v,3u^4v^6, and 3u^2v^5

Abird on top of a 200 ft bridge tower sees a man standing on the lower part of the bridge (which is 50 ft above the ground). the angle of depression from the bird is 26 ̊. how far is the man from the base of the bridge tower? with explanation and pictures .