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. Activity Amount $ 18,600 a. Swing Hard collected S18,600 from customers for lesson services given in February b. Swing Hard sold a gift card for golf lessons for $120 cash in February c. Swing Hard received $5,500 from services provided on account to customers in January d. Swing Hard collected $5,100 in advance payments for services to start in June. e March Swing Hard billed a customer $150 for services provided between February 25 and February 28. The bill is to be paid in