A call center for customer support records the time each customer requires for service and whether the call occurred during the week (Monday through Friday) or during the weekend (Saturday and Sunday). The results are shown in the following table:

Determine the probability that a randomly selected call

a. Was during the week

b. Was less than 20 minutes

c. Was 10 to less than 20 minutes

d. Was more than 20 minutes during the weekend

e. Was 15 to less than 20 minutes or occurred during the weekend

f. Was 5 to less than 10 minutes, given it occurred during the week

g. Occurred during the week, given it was 5 to less than 10 minutes

h. Construct a decision tree for these events.

Time (MinutesWeek Weekend Less than5 5 to less than 10 10 to less than 15 15 to less than 20 More than 20 15 26 4 10 14