Angling for a Laugh - A Pair of Puns

Son 2: "When the timer goes all rotate the pizza 180 degrees."
Me: "Because they're pizza Pis?"*

Son 2: "I was walking home and I saw a car perked perpendicular to the sidewalk."

Son 1: "That's normal."**

References:
*http://en.wikipedia.org/wiki/Radian#Conversion_between_radians_and_degrees

**http://en.wikipedia.org/wiki/Normal_(geometry)