MADISON, Wis. (AP) -- The superintendent of a Wisconsin school district where a student shot his principal six years ago says the nation must confront what's causing school shootings.
Tom Andres leads the Weston School District in Cazenovia. The district was rocked in 2006 when 15-year-old Eric Hainstock came to school with guns and shot Principal John Klang to death.
Andres says the Connecticut school shooting brought back terrible memories of that day. He says he doesn't understand why people need assault rifles but the country should attack the root of the problem and focus on helping troubled people.
He says guidance counselors and police liaison officers need to improve threat assessments. He adds that parents need to more closely monitor their children's exposure to violence through video games and other media.
Read the following SAT test question and then click on a button to select your answer.
for all integers 
If 
is a function defined for all positive integers 
, and 
satisfies the two conditions above, which of the following could be the definition of 
?
