What became a major form of wall decoration during the Romanesque period? Why?

Drum columns

In most parts of Europe, Romanesque columns were massive, as they supported thick upper walls with small windows, and sometimes heavy vaults. The most common method of construction was to build them out of stone cylinders called drums, as in the crypt at Speyer Cathedral.

coordinates of r(b,c)

slope of nm is 0.

step-by-step explanation:

the midpoint of the line joining the points (x₁,y₁) and (x₂,y₂) is given by

the midpoint of the line segment nk is given by

∴r(b,c)

the slope of the line joining the points (x₁,y₁) and (x₂,y₂) is given by

slope of rs is

hence

coordinates of r(b,c)

and slope of nm is 0.