Help me ples 20 point

Wrote and expression for the difference of p and 4

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.

Which strategy is used by public health to reduce the incidence of food poisoning?