Out of $20$ creepy-crawly creatures in a room, $80\%$ are flies and $20\%$ are spiders. If $S\%$ of the total legs belong to spiders, what is $S$? (Note: Flies have 6 legs and spiders have 8 legs.)

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.