What is modern art ? what is postmodern art ? what is contemporary art ? pls need art class i’m stuck

Modern Art includes work produced during the. From the 1860s to the 1970s postmodern art is a body of art movements that sought to contradict some aspects of modernism or some aspects that emerge or developed in its aftermath Contemporary Art is the art of today

perimeter = 2l +2w, divide total perimeter by 2 for total length of 1 side and 1 width

172/2 = 86 (  total for 1 side and 1 width)

86-24 = 62 (since length is 24 ft longer subtract 24 then divide by 2 for width)

62/2 = 31

width = 31 feet

length = 31 +24 = 55 feet

check: 31*2 = 62, 55*2 = 110,  110+62 = 172