Total amount borrowed by college student = $ 2,000
Total interest paid = $123.75
Total amount the student has to pay = $2,000 + $123.75
= $2123.75
Total duration for which the amount is borrowed = 9 months
Total amount he has to pay back in 1 month = 
= $235.9
Therefore, Amount he has to pay in 1 month = $235.9
Multiply 48,000 by 2.3 to get 110,400
She needs to sell $110,400 products next month
7.77/129.5 = 0.06
Therefore the tax rate is 6%
Hope I was able to help :-)