Ionic compounds are formed between a cation, which is usually a metal, and an anion, which is usually a nonmetal. A covalent bond involves a pair of electrons being shared between atoms. I hope this helps you out.
Earth's long-term warming trend can be seen in this visualization of NASA's global temperature record, which shows how the planet's temperatures are changing over time, compared to a baseline average from 1951 to 1980. The record is shown as a running five-year average.
A lava fountain is an example of the amount of heat stored in the Earth. Geysers, lava mountains and hot springs are all natural examples of geothermal energy.
Absorption of heat by breaking down hydrogen bonds
The answer is a the first one.
