HOUSTON -- Jeffrey Skilling didn't lose his temper on the stand on Tuesday, but the ex-CEO appeared to be seething during testimony in the Enron trial.

Federal prosecutor Sean Berkowitz pushed Skilling about bad investments held in off-the-books structures. Prosecution witnesses have said the strategy was used to hide losses.

Skilling occasionally answered with sarcasm or tried to give long explanations, but Berkowitz prompted him for "yes" or "no" or short answers.

The government said Enron's obsession with meeting or beating Wall Street expectations led executives to hide losses and inflate earnings. But Skilling testified on Tuesday that "every company tries to hit their earnings targets."

The Houston-based energy giant collapsed into bankruptcy amid scandal in late 2001.

Skilling and Enron founder Kenneth Lay are charged with fraud and conspiracy.

The federal fraud and conspiracy trial is in its 12th week.

Lay, who was expected to begin testifying next week, gave high marks to Skilling for his testimony so far.

"I think Mr. Skilling did a great job today," Lay said Tuesday.

Skilling faces 28 counts of fraud, conspiracy, insider trading and lying to auditors for allegedly lying about Enron's financial strength.

Lay faces six counts of fraud and conspiracy for perpetuating the alleged scheme after Skilling resigned in August 2001.

They say they did nothing wrong.