Explain/show how you got that answer.
a.150°
b.90°
c.45°
d.30°

82.8 in²

Step-by-step explanation:

The surface area a triangular based pyramid :

Base area + 1/2(perimeter * slant height)

Base = 8 inches ; Slant height = 4.6 inches ; altitude of base measure = 6.9 inches

Base area of triangle :

1/2 * base * height

1/2 * 8 * 6.9

4 * 6.9

Base area = 27.6 in²

The perimeter, P = sum of sides ; (s1 + s2 + s3

P = 8 + 8 + 8 = 24 in

Hence,

Surface area = 27.6 in² + 1/2(24*4.6)

Surface area = 27.6 in² + (12 * 4.6) in²

Surface area = (27.6 + 55.2)

Surface area = 82.8 in²