You and a friend are studying for a quiz. You want to get a higher score than your friend, so you decide to spend exactly $20$ more minutes studying than your friend does. In the graph below, $f$ is the number of minutes your friend spends studying, and $y$ is the number of minutes you spend studying. The relationship between these two variables can be expressed by the following equation: $y=f+20$. **Which of the following statements are true?** [[☃ radio 1]]