Find a line parallel to y=.75x−6 and passes thru (4, 5)

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?

The equation of a parabola is given. y=18x2+4x+20 what are the coordinates of the focus of the parabola?

Find all the angles that satisfy the equation cos(θ)=32