help--new to statistics

#1
i am an undergrad student and just started statistics and already i do not unerstand--please help! see below what i need help with:

the following is a random sample of 90-day futures prices in dollars for 1 oz of silver from the wall street journal issues in may and june of 1997. 4.74, 4.77, 4.87, 4.91, 4.83, 4.72, 4.92, 4.86, 4.97, 4.71, 4.90, 4.93, 4.75, 4.88, 4.79, 4.83, 4.89.

a--construct a stem-and-leaf plot of the data
b--construct a new stem-and-leaf plot of the data by doubling the stem
c--construct a histogram of the data
d--desribe the shape of the histogram
 
#3
You can use Minitab to make the histogram, if you have it.

MTB > set c1
DATA> 4.74, 4.77, 4.87, 4.91, 4.83, 4.72, 4.92, 4.86, 4.97, 4.71, 4.90, 4.93, 4.75, 4.88, 4.79, 4.83, 4.89
DATA> end
MTB > histogram c1