Let's not look at the option and try to solve it.
√x=7
Let's look at this. Square roots are the number that is multiplied by itself to make that number. For example, 2 is the square root of 4, 3 is the square root of 9.
We need to multiply 7 by itself to find x.
7×7=49
So, D. =49.
The answer to the question is b
Percent markup=amountmarkedup/original times 100
amountmarkedup=25-13.5.5=11.5
original=13.5
percent markup=11.5/13.5 times 100=0.85 times 100=85% markup
Here! not sure if it's right but i'm pretty confident. boom