Please choose the correct ending to complete the given sentence: Cars & Other Vehicles: [header] How to measure tongue weight [title] Ensure that the wheels of your trailer are securely blocked to prevent movement. [title] Cut a 5-to 6-foot (1.5 to 1.8 m)-long section of 2 by 4. [title] Lay a pipe across the bathroom scale.

Ending1: [step] Run a wire wiring line across the pipe from the scale to the bowl diameter fittings, then cut clear electrical conduit. Another 5-foot (1.8 m)-long section of 3 by 4 or so is satisfactory. Ending2: [step] Use a tape measure about three times the length of the pipe. [title] Make a square-angled mark on the side of the pipe about halfway along each side. Ending3: [title] Lay a second pipe across a brick. [title] Set both of these 3 feet (0.91 m) apart. Ending4: [title] Sit on the scale's edge and measure both the widest left and right walls of the room and, above the scale, the center which becomes the longest wall. [title] Lay the pipe horizontally across this length and mark where the wall will go, preferably on the upper edge.

Answer format: ending1/ending2/ending3/ending4