Answer:
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Explanation:
All potential and kinetic energy is transferred into heat. Therefore keeping the law of conservation of energy valid. No energy is created nor destroyed only changing shape.
Answer:
The answer to your question is Nonmetals
Explanation:
Nonmetals they are bad conductors of heat and electricity except graphite.
Metalloids they are less conductors of electricity than metals.
Noble gases they conduct electricity.
Halogens they are not metals and do not conduct electricity.
From this information, we conclude that Oxygen and Selenium are nonmetals.
Answer:The frequency of the echo is slightly decreased
Explanation:
Given
speed of boat 
cliff is 
away
when boat is still , suppose t is the time taken by the echo to reach observer on the boat
But as soon as boat starts moving the distance between cliff and boat decreasing and time for echo to reach observer also decreases
and we know 
therefore frequency of the echo slightly decreased.
Am not really sure but what i see is D
