Answer:
D. Because we cannot easily detect them.
Explanation:
Dark matter are called dark because using existing astronomical instruments we are blinded to them. Dark matter and dark energy are difficult to detect and properly observe. As we know that the whole universe is made up of matter, some of the matter do not interact with the electromagnetic radiations which makes undetectable.
Answer:
Positive feedback
Explanation:
If the temperature on Earth starts to lower then a "positive feedback" will start to begin trying to make Earth heat up.
Answer:
A
Explanation:
I believe the answer is A. An object is every color except the color we see, or the color that bounces off of said object. Therefore if a carpet is yellow, the carpet is every color but yellow. Yellow is the color that it rejects, bounces off of it, and the one we see.
Answer : There are basically three subatomic particles that exists; namely proton, neutron and electron.
Please refer the attached chart for the complete comparison.
- Protons are observed to be found in the nucleus of the atom. Which appears at the tiny, dense region at the center of the atom. They have a positive electrical charge of one (+1) and a mass of 1 atomic mass unit (amu).
- Neutrons exists in atoms of all elements they have neutrons located in their nucleus. Unlike protons and electrons, which are electrically charged, neutrons do not have any charge they are found to be electrically neutral. The mass of a neutron is slightly greater than the mass of a proton, which is 1 atomic mass unit (amu) .
- Electron are fundamental particles which does not consist of smaller particles. They are a type of fundamental particles called leptons. All leptons have an electric charge of −1 or 0 . Electrons are observed to be extremely small. The mass of an electron is only about 1/2000 the mass of a proton or neutron, so electrons contribute virtually nothing to the total mass of an atom. Electrons have an electric charge of −1 , which is equal but opposite to the charge of a proton, which is +1 . All atoms have the same number of electrons as protons, so the positive and negative charges "cancel out", making atoms electrically neutral.
Answer:
3%
Explanation:
We have heard about the clean water crisis, but how can that happen if earth mostly covered in water? Even though 70% of the earth is covered in water, most of those water is at ocean and has a high concentration of salt. We can't drink those water because the salt will take more water from our bodies. Freshwater only makes up about 2.5-3% water bodies while the ocean makes up 97% of the rest. Out of 3% freshwater, we have, only 1% of them that easily accessible.