More than likely it is c, because I looked over all the answers and c was the best one for the problem
You paid $4.76 total for 7 notebooks. To figure out how much each individual notebook cost, you divide the total cost by the number of things you bought, so
Cost of One Notebook = Total Cost of Notebooks / Number of Notebooks = $4.76 / 7 = $0.68
This is the unit rate.
To buy three notebooks, you just calculate the total cost of three notebooks at this price point, so
Cost of Three Notebooks = Cost of One Notebook * 3 Notebo0ks = $0.68 * 3 = $2.04
The square root of 64 is 8 because 8x8 is 64
I uploaded the answer to a file hosting. Here's link:
tinyurl.com/wpazsebu
![\huge \bf༆ Answer ༄](https://tex.z-dn.net/?f=%5Chuge%20%5Cbf%E0%BC%86%20Answer%20%E0%BC%84)
Let's solve ~
![\qquad \looparrowright \sf - 7 \sqrt{80 {x}^{4} y {}^{2} }](https://tex.z-dn.net/?f=%5Cqquad%20%5Clooparrowright%20%5Csf%20-%207%20%5Csqrt%7B80%20%7Bx%7D%5E%7B4%7D%20y%20%7B%7D%5E%7B2%7D%20%7D%20)
![\qquad \looparrowright \sf - 7 \sqrt{2 {}^{4} \times 5 \times {x}^{4} \times {y}^{2} }](https://tex.z-dn.net/?f=%5Cqquad%20%5Clooparrowright%20%5Csf%20-%207%20%5Csqrt%7B2%20%7B%7D%5E%7B4%7D%20%20%5Ctimes%205%20%5Ctimes%20%20%7Bx%7D%5E%7B4%7D%20%20%5Ctimes%20%20%7By%7D%5E%7B2%7D%20%7D%20)
![\qquad \looparrowright \sf - 7 \times {2}^{2} \times {x}^{2} \times y \times \sqrt{5}](https://tex.z-dn.net/?f=%5Cqquad%20%5Clooparrowright%20%5Csf%20-%207%20%5Ctimes%20%20%7B2%7D%5E%7B2%7D%20%20%5Ctimes%20%20%7Bx%7D%5E%7B2%7D%20%20%5Ctimes%20y%20%5Ctimes%20%20%5Csqrt%7B5%7D%20)
![\qquad \looparrowright \sf - 28 {x}^{2} y \sqrt{5}](https://tex.z-dn.net/?f=%5Cqquad%20%5Clooparrowright%20%5Csf%20-%2028%20%7Bx%7D%5E%7B2%7D%20y%20%5Csqrt%7B5%7D%20)
Therefore, Option D is correct ~