Answer:
C. At least five mass-extinction events have occurred during the last 500 million years.
Explanation:
- The history of mass extinct is related to the five mass extinctions that are caused over by the 350 million years n which many species have disappeared in there short geologic time.
- A massive extinction is caused in the Permian Triassic extinction event i.e about 250 mn years ago which on an estimate has killed 90% of the species.
- The Cretaceous–Paleogene extinction event that occurred over 66 million years ago is known to have wiped out the dinosaurs and many other species.
Answer:
D. Nitrogen-14 has 7 electrons, 7 protons, 7 neutrons nitrogen-15 has 7 electrons, 7 protons, and 8 neutrons
Explanation:
In an atom, number of electrons is equal to the number of protons. And the number of neutrons is equal to the difference between the mass number of the atom and the atomic number. For Nitrogen 14, electron is 7, proton is also 7 as number of electrons and number of protons are equal. So, the neutron will be 14-7= 7. For Nitrogen 15, electron number is 7 so proton number will be also 7. Neutron number for nitrogen 15 will be 15-7= 8. That's why the answer is option number 4.
DNA<span> contains codes for proteins, which are necessary for the growth and functioning of an </span>organism<span>. </span>DNA<span> separates into long single strands that make up each part of an</span>organism<span>. </span>DNA<span> produces the energy an </span>organism<span> needs in order to grow. </span>DNA<span> folds into the nucleus of each of the </span>cells<span> of an </span>organism<span>.</span>
True, pulmonary arteries carry the blood from the heart, while pulmonary veins return the blood to the heart.
When a hostname is configured through the Cisco CLI, some naming conventions must be follows.
These naming conventions are as follows:
1- The name of the host must always begin with a letter
2- The name of the host cannot contain any spaces
3- The length of the hostname should always be less than 64 letters
