Answer:
Explanation:
This is a problem based on time dilation , a theory given by Albert Einstein .
The formula of time dilation is as follows .
t₁ = 
t is time measured on the earth and t₁ is time measured by man on ship .
A ) Given t = 20 years , t₁ = ? v = .4c

=1.09 x 20
t₁= 21.82 years
B ) Given t = 5 years , t₁ = ? v = .2c

=1.02 x 5
t₁= 5.1 years
C ) Given t = 10 years , t₁ = ? v = .8c

=1.67 x 10
t₁= 16.7 years
D ) Given t = 10 years , t₁ = ? v = .4c

=1.09 x 10
t₁= 10.9 years
E ) Given t = 20 years , t₁ = ? v = .8c

=1.67 x 20
t₁= 33.4 years
All the inhabitants of a particular place or town, area or country
The correct answer is Dr. Patel, a cardiologist, presents her findings on heart disease.
A cardiologist is a heart doctor, so he would be the highest authority to speak about heart disease. The others are all amateurs in their businesses.
Answer: The answer is A
Explanation: I took that test already
Xenon can be used for things like high pressure arc lamps for motion picture projection, in high pressure arc lamps to produce ultraviolet light and photographic flashes. It is also used to help the radiation detection, for example X-ray counters.
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