A thief who jumped into a woman’s car and robbed her at knife-point in January has been given 90 days in jail. Isaac Brian Whitman, 27, has been sentenced for the incident which happened in the Walmart parking lot.According to the arrest warrant against Whitman, the female victim was “sitting in her vehicle at Walmart when she was approached by the suspect who opened the passenger-side door and entered her vehicle. He asked her if she had any money and she said no and he saw her wallet sitting on her seat between her legs.”