Any object that is spherical in shape would best represent a true scale model of the shape of the Earth. Examples are ping pong balls, billiard balls, marble and other smooth spherical objects. The shape of the Earth is called the oblate spheroid. The "oblate" would refer to an oblong shape and "spheroid" would refer to an almost spherical shape. The earth has on almost spherical shape and has a slightly oblong appearance. The diameter from the South pole to the north pole was measured to have a value of 12714 km while the diameter of the equator is approximately 12756 km. As you can see, the values are not equal. This makes the earth not a perfect sphere.
A wave that is oscillation of matter.. such as a water ripples
I DONT know FiGURE it out YOURSELF