Provary US$.$ interstate highways are numbered $1-99.$ Odd numbers $($like the $5$ or $95)90$ north$/$south$,$ and evens $($ike the $10$ or east$/$west$.$ Auxilury highways ave rumbered $100-999,$ and service the primary highway indicated by the rightmost two digits. T Given a tighway rumber, indicate whether it is a primary pr ausilary highway if aissiary, indcate what primary highway it serv indicahe the $($premary$)$ highway runs north$/$south or eastwest