From your description, it seems there are two forces acting in opposite directions: 1. A force of 15 N in one direction. 2. A force of 5 N in the opposite direction. 3. block= 20kg The acceleration of the block shown in the figure below (no other horiznotal forces are present besides the two shwon in the figure) is equal to * 0 m/s2 * 0.5 m/s2 * 1 m/s2 * none of the numerical values shown