Which statement correctly describes the relationship between the graph of f(x)=2xf(x)=2x and the graph of g(x)=f(x)−4g(x)=f(x)−4 ?

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?