HELP

what is this

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 $s$?

I’m still confused on how to work the percentages

Aline has a slope of negative 1/4 the past two points -5/4 and 1 what is the equation of the line