Answer: 
Explanation:
Given
Cross-sectional area of wire 
Extension of wire 
Extension in a wire is given by
where, 
for same force, length and material
Divide (i) and (ii)
Answer:
3 Cycles
Explanation:
Every cycle on a cosine function are marked by the completion of 5 key points when moving along the x-axis:
(5, 0, -5, 0, 5)
This cycle has a frequency of 2, occurring once every second, thus answering our question easily.
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Answer:
Animals are treated as humanely as possible.
Explanation:
Ethical guidelines relating to animals are laid down principles or laws that guide against the maltreatment of animal in any way during or for a research. As the use of some animals for various researches can not be over emphasized, because of the close proximity between their body tissues to that of humans.
The ethical guidelines enforce treating animals as humanly as possible or achievable. This ensure appropriate handling and treatment of the animals.
