Answer:
1. Prepare the entry in November for the receipt of the subscriptions.
November 30, 2017
Dr Cash 147,600
Cr Unearned subscription revenue 147,600
Unearned subscription revenue = $20 x 7,380 = $147,600
2. Prepare the adjusting entry at December 31, 2017, to record subscription revenue in December 2017.
Dr Unearned subscription revenue 12,300
Cr Subscription revenue 12,300
Subscription revenue = $147,600 / 12 months (only December) = $12,300