Element
An element is a pure substance that cannot be broken down into other substances, an element is made up of only one type of atom.
Hope this helps :)
I believe true because the Precambrian is the first geologic time, going back 4600-570 years ago, meaning it should contain the earliest of things.
The length of a vessel is directly proportional to its resistance: the longer the veessel, the greater the resistance and the lower the flow. As with blood volume, this makes intuitive sense, since the increased surface area of the vessel will impede the flow of blood.
They are composed of actin, troponin, tropomyosin, and myosin
