1) The first commercial mobile phone, the Motorola DynaTAC 8000X, was released in 1983 and weighed nearly 2 pounds.

2) Mountains are formed through various geological processes, including tectonic plate movements, volcanic activity, and erosion.

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

4) The word "yesterday" contains three vowels: E, A, and A.