Answer:
67%
Step-by-step explanation:
There are a few methods to finding the percent of a number. You can use proportions:

The 'percent' is the percent of the fraction that you are looking for, or 48/72.
Cross-multiply: 72x = (48)(100) or 72x = 4800
Divide both sides by 72: 72x/72 = 4800/72
Solve for 'x': x = 66.6666...
Round 66.666.... to the nearest percent: 67%
Every positive number has two square roots - a positive and a negative (unless the value is 0).
The length of something can only be a positive number and since there is only one positive square root, there is only one answer.
Answer:
I believe the answer is a.
Do you have a picture I can use for reference?