Please choose the correct ending to complete the given sentence: Sports and Fitness: [header] How to find true north without a compass [title] Place a stick upright in the ground so that you can see its shadow. [step] Alternatively, you can use the shadow of a fixed object. Nearly any object will work, but the taller the object is, the easier it will be to see the movement of its shadow, and the narrower the tip of the object is, the more accurate the reading will be.

Ending1: Make sure the shadow is cast on a level, brush-free spot. [title] Mark the tip of the shadow with a small object, such as a pebble, or a distinct scratch in the ground. Ending2: [substeps] Compass pencils are disposable, yet quite powerful. Brightly colored pencils can be found in specialty shops for accessories. Ending3: [substeps] The height is a big factor in determining how tall your compass needle is. A compass needle is a cube of metal that sticks in the ground. Ending4: [title] Hold the compass at the center of your field of view. [step] Use all three methods of placing your compass that you can think of : [substeps] Place your compass in a straight line up towards the sky.

Answer format: ending1/ending2/ending3/ending4