Could you please work me thought this stem and leaf step by step

1. Here a stem-and-leaf display for course grades of an algebra class:

0 | 79

1 |

2 |

3 | 2

4 |

5 | 38

6 | 3679''7 | 0'' means 70

7 | 001389

8 | 03466789

9 | 011257

1. How many students earned Bs (course grades from 80 to 89)?
2. Which value is greater: the mean or the median? How do you know?
3. How many students would you estimate stopped participating in the class during the quarter? In the plot, what are their course grades called?