Unlimited lives:
Load or reset the game, then execute the following BASIC command before running or restarting the program. 

POKE 2242,165 
Unlimited lives (alternate):
Load or reset the game, then execute the following BASIC command before running or restarting the program. 

POKE 2688,234 
Unlimited lives (alternate):
Load or reset the game, then execute the following BASIC command before running or restarting the program. 

POKE 32897,165 
Invincibility:
Load or reset the game, then execute the following BASIC commands before running or restarting the program. 

POKE 2242,234
POKE 2234,234