For several years, Graham has gathered data on students who own a computer and on their performance on a typing-speed test. He creates the linear model y = 3.8x + 17.4 where y represents the typing speed, in words per minute, of a student and x represents the number of years the student has owned a computer. According to Graham’s model, what is the approximate speed of a student who has owned a computer for three years? 21 words/min 29 words/min 56 words/min 64 words/min