Jenny drew a figure in art class. does it have rotational symmetry? if yes, what is the angle of rotation.

How do you use the elimination method for this question? explain, because i really want to understand!

Select the number of ways in which a line and a circle can intersect

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 $s$?