There are 7 oak trees currently in the park park workers had to cut down 2 oak trees that were damaged how many oak trees will be in the park when the workers are finished

The sum of two numbers is 12 and their difference is 18 what are the two numbers

Ten times the square of a non-zero number is eqaul to ninety times the number

The distribution of the amount of money spent by students for textbooks in a semester is approximately normal in shape with a mean of $235 and a standard deviation of $20. according to the standard deviation rule, how much did almost all (99.7%) of the students spend on textbooks in a semester?