I cant see it or else i would help sorry..
Answer:
1, 33.3
2, 81.9
3, 240
4, the farmer sold 33.3 of his crops
5, 750 students are enrolled.
With pythagorean theorem and working backwards, you do 8100-1225 to get 6875, you then get the square root of that to get x=82.91 or rounded to 82.92