1. her boyfriend's this built jock who's a big deal on the varsity sports circuit at school
What does jock and circuit mean here?
2. maybe it is a lottery, but the universe makes it all even out in the end
What does out mean here?
3. "I can't wear that, Mom," I whined. "You'll hardly notice them," said Mom, trying to be cheerful. "They look like headphones." "Headphones? Look at them, Mom!" I said angrily. "I'll look like Lobot!" "Which one is Lobot?" said Mom calmly. "Lobot?" The ear doctor smiled as he looked at the headphones and made some adjustments. " The Empire Strikes Back? The bald guy with the cool bionic radiotransmitter thing that wraps around the back of his skull?" "I'm drawing a blank," said Mom.
What does I'm drawing a blank mean here?