Answer:closed systems
Explanation:
A closed system is one in which matter does not enter or leave the system but there is exchange of energy between the system and its environment. In a closed system, the principle of energy conservation applies. The principle of energy conservation states that energy can neither be created nor destroyed but is converted from one form to another. An example of a closed system is a reaction vessel whose lid is closed.
Answer:
7. I and III only.
Explanation:
Only portions of the electromagnetic spectrum is visible to the human eye. Electromagnetic radiation in this range of wavelengths is called visible light which have wavelengths from about 390 to 750 nm that is; ultraviolet light and visible light.
The answer is
Pitch of the buzzer increased (higher tone) as it moves towards the observer
Resultant displacement between the base camp and the cave will be 7.211 km
Displacement is a vector quantity that refers to "how far out of place an object is"; it is the object's overall change in position.
Her resultant displacement can be calculated using Pythagoras theorem
= 
= 52
H = 
= 7.211 km
Resultant displacement between the base camp and the cave will be 7.211 km
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