<span>The element bromine has two isotopes: Br-79 and Br-81, with a 50%-50% isotopic abundance. Statistically, 25% of bromine molecules will be Br79-Br79, 25% will be Br81-Br81 and 50% will be Br79-Br81. This is equivalent to a ratio of 1:1:2 or 1:2:1. The peaks in a mass spectrum just like chromatography reflect this relative abundance of different isotopic combinations.</span>
Answer:
The first flowering plants appeared in the Mesozoic era, not the Paleozoic era.
Explanation:
The Mesozoic era was an era where numerous organisms started to develop in very unique and more advanced ways, both the animals and the plants. In the last period of the Mesozoic, the Cretaceous, the first flowering plants started to appear on the scene. This was revolutionary trait of the plants, and soon these plants started to occupy more and more space and became one of the dominant organisms on the planet. Other important evolution that took place in this period are the appearance of the dinosaurs and the mammals, both becoming the dominant animals on the planet, first the dinosaurs, after that the mammals.
A proton has positive charge of 1, that is, equal but opposite to the charge of an electron. A neutron, like the name implies, is neutral with no net charge. The charge is believed to be from the charge of the quarks that make up the nucleons (protons and neutrons).
A tomato is apart of the fruit family:) hope this helps!
