check the picture below, that's pretty much the same block, or "rectangular prism", with a width of 10, length of 5 and height of 1.
so anyhow, is really 6 rectangles stacked up to each other at the edges, so, we can simply get the area of each of those rectangles, add them up and that's the surface area.
front and back, two rectangles of 5x1
left and right, two rectangles of 1x10
top and bottom, two rectangles of 10x5

70(0.21) + 99(0.23) + 91(0.23) + 90(0.33)
= 14.7 + 22.77 + 20.93 + 29.7
= 88.1%
(4v-3w)∧2, Its to the second power so take the exponent 2 and put it on the variables and coefficients so you would have (4∧2)(v∧2)-(3∧2)(w∧2). Then you would do the math and get 16v∧2-9w∧2 than you would add the like terms so you have 25v∧2w∧2.