Vehicle Entering Through Highway

(a)The operator of any vehicle shall stop at the entrance to a through highway and shall yield the right of way to other vehicles which have entered the intersection from the through highway or which are approaching so closely on the through highway as to constitute an immediate hazard and shall continue to yield the right of way to such approaching vehicles until such time as he can proceed with reasonable safety.

(b)Said operator having so yielded may proceed and the operators of all other vehicles approaching the intersection on the through highway shall yield the right of way to the vehicle so about to enter or cross the through highway.