For each of the following independent situations, prepare journal entries to record the initial transaction on September 30 and the adjustment required on October 31.
a. Hockey Helpers paid $4,000 cash on September 30, to rent an arena for the months of October and November.
b. Super Stage Shows received $16,000 on September 30, for season tickets that admit patrons to a theatre event that will be held twice (on October 31 and November 30).
c. Risky Ventures paid $3,000 on September 30, for insurance coverage for the months of October, November, and December.