Rush's Pasta & Pizza Employs Sigfried as a Delivery Driver

Rush's Pasta & Pizza employs Sigfried as a delivery driver.Rush's guarantees that an order will be delivered within thirty minutes or there is no charge,and insists that its drivers meet the limit.One night,while making a delivery,Sigfried is caught in a traffic jam.To deliver the order within the thirty-minute time limit,Sigfried drives onto a sidewalk and hits Tanya,a pedestrian.Is Rush's liable to Tanya for her injuries Is Sigfried liable to Tanya Why or why not