The following trial balance has been prepared from the ledger of Obelisk Corporation at December 31, 2017, following its first year of operations.

Additional information:

a. Obelisk assumed $100 of long-term debt during the year.
b. Obelisk issued common shares for equipment, $40. Other equipment was purchased for $120 cash. No equipment was sold during the year.
c. Land costing $30 was purchased, then sold during the year for $50.
d. Some borrowings were repaid during the year for $20 cash.
e. The company declared dividends of $15 during the year.

Required:
1. Calculate retained earnings at December 31, 2017.
2. Prepare a statement of cash flows.
3. Explain what the statement of cash flows tells you about Obelisk

Corporation at December 31, 2017.