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)

d. new methods of assembly are introduced.

explanation:

this allows for the goods to be made on a larger scale. not faster because now it is shown to be made better, hence the greater productivity in the question. it is calling for something new to be introduced.