The four inner planets share several features in common.
(Mercury, Venus, Earth and Mars)
They are called terrestrial planets because they have solid, rocky surfaces roughly similar to desert and mountainous areas on the earth.
Matter can be many things, but is mostly made of atoms. Atoms are small things that cannot be seen directly, as lights either passes through it or alters it. However, we know that atoms are made of 3 parts, those being the proton, neutron, and electron.
Protons have a positive electromagnetic charge.
Neutrons have no charge.
Electrons have a negative charge equal to the protons positive charge.
Protons and neutrons make up what's called the nucleus, which is orbited by the electrons.
Protons and neutrons also share another thing in common, that being their composition.
Until relatively recently, we thought that these were the smallest particles in the universe, and indestructible. However, modern discoveries have revealed that they are actually made of quarks and gluons.
These are actually indestructible, being part of the group that is elementary particles.
To measure the fluids that you will be using such as water or other chemicals if your mixing them and they have to be precise measurements
Structural constraint is the answer :)
4. Grass - Caterpillar - Hedgehog - Fox
5. Caterpillar, Rabbit, Mouse.
6. Cougar and Fox.
7. Bacteria
8. The bird, hedgehog, Fox and cougar would be effected since the Hedgehogs and birds would soon die out due to the loss of their food. Once they die out, the cougar and Fox would have no predators left to eat.