81 degrees
1 degree = 2 pi / 360
81 degrees = 162 pi / 360
=9 pi / 20
L (arc) = radius x angle
= 10 x 9 pi / 20
90 pi /20
9/2 pi : D
The answer is D
<span>Indefinite pronouns may replace nouns used as subjects, predicate nouns, direct objects, indirect objects, objects of a preposition, and appositives.</span>
Surface area of a square pyramid is the area of the base + 4 times the area of one of the slanted sides.
Area of base = side length * side length
Area of side = (1/2) * side length * slant height
Don't forget that you have to multiply the area of the side by 4!
Step 1: 12 x 12 = 144
Step 2: 12 x 20 = 240 divided by 2 = 120
Step 3: 144 + 120 x 4
