Is the square root of 144, 12?

Bella want to know what the students at her school think of her show. which is the best group to survey to find this information a. go to the mall and ask all of the students she recognizes from school b. ask her viewers to call in durning an episode of the show c. get a list of students at her school from the office and use a random number generator to pick 30 of them d. get a list of students at her school from the office and pick the first 30 students on the list

I’m still confused on how to work the percentages

The amount cami raised during last year’s charity walk, $45.50, is 7/10 of the amount she raised this year. which equation represents n, the number of dollars she raised this year?