Laurentia, also called the North American Craton, is a huge continental craton. It<span> forms the ancient </span>geological<span> core of the </span>continent of North America.<span> It is made up of present day North America and Greenland. About 300 million years ago, it collided with the southern hemispheric continent of </span>Gondwana<span> and formed the supercontinent called Pangaea.</span><span> </span>
If it is just a reseach investigatory project, you could monitor it by using different variables (controlled), acurate measuring devices and camera for documentations
Answer:
See explanation
Explanation:
1) There are two main types of waves;
Mechanical waves and electromagnetic waves.
Mechanical waves usually require a medium for propagation, e.g sound, waves on a spiral spring, etc
Electromagnetic waves do not require a medium for propagation e.g microwaves, x-rays etc
2) The phenomenon is known as refraction. Refraction occurs at the boundary between two media because of the change in the speed of a wave as it moves from one medium to another.
Answer:
In a polar covalent bond, the electrons are unequally shared by the atoms and spend more time close to one atom than the other.
Explanation: