Martina estimates that the surface area of a rectangular prism with a length of 13.2 feet a width of 6 feet and height of 8 feet is about 460 square feet is her estimate reasonable explain your reasoning my question is that if her estimate is reasonable ? show work

Lizette is training for a marathon. at 7: 00 she left her house and ran until 8: 30, then she walked until 11: 30. she covered a total distance of 18 miles. her running speed was six miles per hour faster than her walking speed. find her running and walking speeds in miles per hour.