I have to displacment problems that i cant get right. While John is traveling along a straight interstate highway, he notices that the mile marker reads 233. John travels until he reaches the 155-mile marker and then retraces his path to the 172-mile marker. What is John's resultant displacement from the 233-mile marker? I thought the answer for this one would be 61 but it is marked wrong. Bob walks 57 m and then he walks 125 m. What is Bob's displacement if he walks east then west? I thought the answer for this one would be 68 but it is marked wrong.