The following transactions are February activities of Swing Hard Incorporated, which offers indoor golfing lessons in the northeastern United States.
If revenue is to be recognized in February, indicate the amount. If revenue is not to be recognized in February, explain why.

Activity Amount or Explanation
a. Swing Hard collected $15,000 from customers for-
lessons given in February.
b. Swing Hard sold a gift card for golf lessons-
for $150 cash in February.
c. Swing Hard received $4,000 from credit sales-
made to customers in January.
d. Swing Hard collects $2,250 in advance-
payments for golf lessons to start in June.
e. Swing Hard bills a customer $125 for-
golf lessons given between February 25 and February 28.
The bill is to be paid in March.