Answer:
Vacuum
Explanation:
A vacuum is usually defined as a space in which there is an absence of matter. It can also be said that there is an extremely low amount of pressure due to which the particles present in it are not affected by any type of process that occurs in space. The value of pressure is lower than the value of normal atmospheric pressure.
For example, sound cannot travel in space because there is no medium such as water and air through which the sound waves can propagate.
Answer:
The answer is by proving that gravity and inertia working together explained the motions of planets and their moons.
Explanation:
<span>The question is asking us to fill in the gaps in the following sentence: When a person loses consciousness due to a head injury from a car crash, the (gap) keeps the body functioning by regulating the flow of information between the brain and the rest of the body. The best answer is that the gap should be filled by "autonomous nervous system" - this system is the one that is not controlled consciously, but one that is working in the background to make sure our body functions work properly.</span>
Answer:
B. Hardness
Explanation:
Physical properties of a substance is defined as the properties which can be observed or measured without changing the composition of matter.
Physical properties include odor, appearance, color, texture, boiling point, melting point and many others.
Hardness is a physical property of a substance as it describes the resistance of substance to deformation and can be observed by simple touch or without changing the composition of matter.
While reactivity, toxicity and flammability are chemical properties of substances that change one type of matter into another type.
Hence, the correct option is B.
Answer:
They contain protein fibres that can contract when energy is available, making the cells shorter.