In late 1995, a Gallup survey reported that Americans approved sending troops to Bosnia by 46 to 40 percent. The poll did not mention that 20,000 U.S. troops were committed to go. A CBS News poll, mentioned the 20,000 figure and got the opposite outcome--a 58 to 33 percent disapproval rate. Briefly explain why the mention of the number of troops would cause such a huge difference in approval results?