Find the area of the triangle to the nearest tenth square unit. Use a calculator. a =3 ft, b = 4 ft, c = 5 At O 1.1 42 O 3.5 ft2 150.3 ft2 O 6.0 At2 53.5 ft2 5. Choose the best answer. Find the measure to the nearest tenth of the unknown angle given a = 8, b = 13, c = 20 . Use a calculator. Find mLC O ~ 97.9' ~ 137.9 O ~ 45.5 O ~143.4