A test for being drunk
A police officer pulls over this guy who had been weaving in and out of the lanes.

He goes up to the guy's window and says, "Sir, I need you to blow into this breathalyzer tube."

The man says, "Sorry officer I can't do that. I am an asthmatic. If I do that I'll have a really bad asthma attack."

"Okay, fine. I need you to come down to the station to give a blood sample." "I can't do that either. I am a hemophiliac. If I do that, I'll bleed to death."

"Well, then we need a urine sample."

"I'm sorry officer I can't do that either. I am also a diabetic. If I do that I'll get really low blood sugar."

"Alright then I need you to come out here and walk this white line."

"I can't do that, officer."

"Why not?"

"Because I'm too drunk to do that!"

Brain or muscles?
The strong young man at the construction site was bragging that he could outdo anyone in a feat of strength. He made a special case of making fun of one of the older workmen. After several minutes, the older worker had had enough."Why don't you put your money where your mouth is," he said. "I will bet a week's wages that I can haul something in a wheelbarrow over to that outbuilding that you won't be able to wheel back.""You're on, old man," the braggart replied. "Let's see what you got."The old man reached out and grabbed the wheelbarrow by the handles. Then, nodding to the young man, he said, "All right. Get in."