Answer:
A, C, D
Step-by-step explanation:
1) A triangular pyramid has the same number of faces as vertices: 5
2) C - The sum is 5 + 6 =11
3) D - Euler's Formula tells us that if we add the number of faces and vertices together and then subtract the number of edges, we will get 2 as our answer.
V solid = π *

* 13 / 3 + π *

* 2 = 3.14 * 25 *13 / 3 + 3.14 * 50 = 340.16 + 157 = 497.16 ≈ 497.20 cubic centimeters;
A healthy 140 pound boy needs between 2,000 to 2,400 calories a day.
Hope that helps :)
You have to find the cos of angle A, so use the Pythagorean equation and trig laws to find the other side of the triangle created by angle A. 3^2 + x^2 = 5^2. x=4. This means cos(A) = 4/5). Make both cos (A) and cos (B) have equal denominators, and add. 148/185 + 60/185 = 208/185. This answer is correct, though it doesn’t appear to be any of the answers you wrote, so either those answers are wrong or you wrote something incorrectly in the problem.