This means that a single carbon atom can form up to tetravalent bonds with other atoms
Reading through the entire investigation before beginning the procedure can help prevent accidents by giving you the knowledge of what to do beforehand and preparing you for what is to come.
Answer:
Option D, the "biological ladder"
Explanation:
The food chain is the network of organism in which all are dependent on each other for their food, energy source and survival.
The circle of life depicts the time frame starting from origin of a life form till its death and the intermediate stages.
The tree of life basically determines which organism has evolved from which other organisms.
The biological ladder represents the development of species from simple form to a much complex form.
Hence, option D is the right metaphor
A volcanologist is a geologist who studies the process involved in the formation of a volcano. He also studies the eruptive nature of the volcano along with their current and historic eruptions.
The tasks done by a volcanologist do to study volcanoes are =
1. use autoclaves to imitate the interior of a volcano
2. simulate volcanic explosions with computer programs
3. study lava samples
4. listen to the sounds of the interior of a volcano