In the absence of air resistance and friction, what will happen to the velocity of an object going at 20 m/s e?

In the absence of any other forces, the object will continue to move at 20 m/s E.

In fact, Newton's second law states that the resultant of the forces acting on an object is equal to the product between the mass and the acceleration of the object:

therefore, if there are no forces acting on the object, the term on the left is zero, and the acceleration of the object is zero as well. This means that the object will continue its motion with constant speed, and in the same direction.