Answer: This coil will not be enough to complete the job.
Step-by-step explanation:
The circumference of the coil of wiring can be calculated with:
Where r is the radius and
The radius can be calculated by dividing the diameter by 2. Then:
Convert 9 inches to yards (1 yard=36 inches):
Substitute this radius into the formula:
Since there are 21 circles of wire, you need to multiply by 21:
The coil has 32.97 yards of wire and Alex needs 34 yards, therefore, this coil will not be enough to complete the job.