An ideal heat engine exhausting heat at 77^@Cis to have a 30% efficiency. It must take heat at

An ideal heat engine exhausting heat at 77^@Cis to have a 30% efficien

1.	An ideal heat engine exhausting heat at 77^@Cis to have a 30% efficiency. It must take heat at
Answer» `127^@C` `227^@C` `327^@C` `673^@C` ANSWER :B