> Maturity risk premium help?

Maturity risk premium help?

Posted at: 2014-12-05 
The wall street journal reports that the yield on a 9-month treasury bond is 2.3 percent, the yield on a three year treasury is 2.9 percent, and the yield on a 10 year treasury is 4.3 percent. With no liquidity premium associated with treasuries, there is a maturity risk premium. What is it?

I need help with this homework question. Will someone show me how to get the answer?