What is the smallest degree of rotation that will map a 20-gon onto itself?

Plz.yesterday, the snow was 2 feet deep in front of archie’s house. today, the snow depth dropped to 1.6 feet because the day is so warm. what is the percent change in the depth of the snow?

Graph the equationy=x^2 -[tex]y = x^{2} - 2[/tex]

Rewrite so the subject can be y in the formula d=m-y/y+n