HELP PLSS LAST QUESTION BEFORE IM DONE WORTH BRANLIEST IF U GET IT RIGHT

Find the vertex of the function given below y=x^2-6x+1

One line passes through (-7,-4) and (5,4) . another line passes through the point (-4,6) and (6,-9)

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?