Venus Petroleum owned the following unproved property at 12/31/79:

• Significant Leases:
   Lease A: $470,000, Impairment: $250,000
   Lease B: $720,000, Impairment: $270,000
• Insignificant Leases:
   Lease C: $100,000
   Lease D: $85,000
   Lease E: $80,000
   Lease F: $70,000
   Total Cost: $335,000, Total Impairment: $100,000

Requirement:
 Prepare journal entries for 2080, assuming the following events:
 a. Lease A was sold for $480,000.
 b. Lease B was fully impaired.
 c. Proved reserves were found on Lease C and Lease F.