A 20 ft ladder is leaned aginst a verticals wall the distince from the foot of the ladder to the wall is 5 feet

b=5sqrt(15)

Explanation:

In this situation, this creates a right triangle

the 20 is c, the 5 is a

a^2+b^2=c^2, 25+b^2=20^2, b^2=375, b=5sqrt(15)

the following sets of characteristics describe what we know about the outer plants is c. rocky surface, closet to the sun and larger in size