1) The Earth's core is primarily composed of iron and nickel and is as hot as the surface of the sun.

2) The fastest recorded serve in tennis was achieved by Sam Groth at 163.7 miles per hour (263.4 kilometers per hour) during a tournament in 2012.

3) The corpse flower, or titan arum, is known for its unpleasant smell, often compared to that of rotting flesh.

4) The Edelweiss flower, found in the European Alps, is known for its beauty and is often associated with mountaineering and alpine culture.