Answer: Compounds.
Explanation:
Compounds are formed when an unstable element combines with other elements, they do this by sharing electrons within their outmost shell. Compounds forms when there is a chemical bonding between two or more elements. Examples of compounds includes carbon dioxide (C, O) water (H and O), Sodium chloride (Na, Cl), methane, etc.
The greenhouse effect is rightly called that because greenhouses allow heat to enter, but doesn't allow heat to leave, which warms plants.
On earth however, it's much bigger. Our own atmosphere acts similarly to this; it allows heat in, but doesn't allow it to leave which heats up the planet and causes global warming.
The Doppler effect doesn't just apply to sound. It works with all types of waves, which includes light. Edwin Hubble used the Doppler effect to determine that the universe is expanding. Hubble found that the light from distant galaxies was shifted toward lower frequencies, to the red end of the spectrum. This is known as a red Doppler shift, or a red-shift. If the galaxies were moving toward Hubble, the light would have been blue-shifted.
Ocean water freezes just like freshwater, but at Lower temperature. Fresh water freezes At 32°F but see water freezes at about 28.4°F because of the salt in it it can be melted down to use as drinking water
