Answer:
a)11cm
b)49.5cm²
Step-by-step explanation:
to find the perimeter you use the formula
o/360×2piR
since 2pi R=18pi cm,to find the radius you cancel pi from both sides 2r/2=18/2...so the radius is 9cm
therefore the perimeter will be:
70/360×2×22/7×9
27720/2520
=11cm
then to find the area you say
o/360×pi R²
70/360×22/7×9²
124740/2520
=49.5cm²
I hope this helps
