Answer:
a.
Step-by-step explanation:
the area of a whole circle (360°) is
pi×r²
in our case
pi×10² = 100pi
but here we don't need the full circle. we only need a fraction of the whole circle : 128/360
so, the area of the sector is
100pi × 128/360 = 100pi × 16/45 = 20pi × 16/9 =
= 111.7010721... cm² ≈ 111.7 cm²
