13. When a trailes dives to the tecenew dock the tecevet opens the doon and staits unloading the fieight only aftet A The truck is sately backed in S The wheel chocks are placed in tront of the rea wheels C. The driver comes inside with the vehile's keys D. The dock plate has been raised and lowered E. All of the above F. None of the above 14. Wheel chocks are used for the following purpose: A. Snow removal in the winter B. Holding up the roll up door C. Unloading the dock plate D. Blocking the front wheels of the trailer E. None of the above 15. The driver of the recerving trailer comes inside when the truck is being received for the following reason: A. To check on the freight