The following stem-and-leaf chart from the Minitab software shows the number of units produced per day in a factory.

a. How many days were studied?
b. How many observations are in the first class?
c. What are the minimum value and the maximum value?
d. List the actual values in the fourth row.
e. List the actual values in the second row.
f. How many values are less than 70?
g. How many values are 80 or more?
h. What is the median?
i. How many values are between 60 and 89,inclusive?