A three-quarter inch service line is tapped on a water main. The corporation stop should be installed__________________.

The installation of a corporation stop at an angle between the top and side of the main is the most appropriate choice. This angle allows for proper access to the service line while maintaining the structural integrity of the water main. By positioning the corporation stop in this manner, it ensures a good seal and reduces the risk of air entrapment or potential backflow issues. Additionally, this angle facilitates easier operation and maintenance of the valve, promoting efficient water flow from the main to the service line.

Other positions, such as vertically along the side of the main, could create improper stress on the water main, leading to potential failures. Installing it directly above the main could complicate future repairs and might not allow for an efficient connection. A horizontal installation could disrupt the flow and create problems with sediment buildup in the service line, which can lead to clogging. Thus, the angled installation strikes the best balance for functionality and reliability in water service connections.