Please choose the correct ending to complete the given sentence: Sports and Fitness: [header] How to find out how much time is left before sunset [title] Find the location of the sun. [step] This method will work best if the sky is clear and there are no clouds. However, if it's cloudy, or the sun is obstructed by trees, you may have to approximate.

Ending1: In this case, you will probably need a tripod or two. [title] Take a piece of string and stretch it taut across the sky to the horizon. Ending2: [substeps] If it is cloudy and you can see a vague outline of the sun, you can still do the measurement between the horizon and the sun. There will be a haze around the sun in the clouds: use that haze as the position of the sun. Ending3: [substeps] Even if there is no obvious cloud cover around the sun, find the sun's position without any trees. In the areas where a lot of people travel, there is usually low visibility, so it's not the most apparent feature. Ending4: [substeps] The sun's rays are created by the heat from the sun itself, so it will be unable to enter the sky. It is common for the sun to lower itself into the sky, gradually increasing its emission during cloudy weather.

Answer format: ending1/ending2/ending3/ending4