Ted puts songs A B and C on shuffle play. How many possible orders of songs can there be

One of the same side angles of two parallel lines is 20° smaller than the other one. find the measures of these two angles.

Anyone? 15m is what percent of 60m; 3m; 30m; 1.5 km?

The area of a rectangle is 10 cm^2. one side of the rectangle is x cm. express the perimeter of the rectangle in terms of x and show that this rectangle cannot have a perimeter of 12 cm. the perimeter of the rectangle in terms of x is __ cm