Answer: cos(54) because the cosine is = to the sine between two complementary angles and 36 + 54 = 90, which means they are complementary.
SA pyramid+SA rectangular prism= total SA
Total SA= Area of the base+ area of the four rectangles+area of four triangles
Total SA= length^2+length*width*4+1/2(slant height)(length)*4
length=12, width=8, slant height=10
Total SA= (12)^2+4(1/2*12*10) +4(12*8)=768cm^2
so C is correct.
The probability of it showing a 1 is 1/6 and the probability of it showing an even number on the second roll is 3/6.