Can someone me with 6b i don't understand it thx if you can

The surface area (sa) of a cube with a as the length of each of its sides is given by the formula . if the surface area is known, how can you rewrite the formula to find its side?

There is a spinner with 14 equal areas, numbered 1 through 14. if the spinner is spun one time, what is the probability that the result is a multiple of 2 or a multiple of 5?

Ricky takes out a $31,800 student loan to pay his expenses while he is in college. after graduation, he will begin making payments of $190.66 per month for the next 30 years to pay off the loan. how much more will ricky end up paying for the loan than the original value of $31,800? ricky will end up paying $ more than he borrowed to pay off the loan.