Answer:
35 feet.
Step-by-step explanation:
To find this, we will need to use the Pythagorean theorem to solve for the diagonal length. Call this diagonal length 'd'.
d² = 21² + 28²
d² = 1225
d² = 35.
Thus, the diagonal length is 35 feet.
The answer is B) 20
Because you have 5 brands and you combine each with the 4 others, so 5*4=20
3.15 /7 = 0.45
3.20/8 = 0.40
4.10/10 = 0.41
4.80/16 = 0.3
Answer is 1. 7 stamps worth 3.15