The efficiency of the first Carnot engine is
n1 = 1 - Th/T
The efficiency of the second Carnot engine is
n2 = 1 - T/Tc
The total efficiency of the engines put in series is
n = 1 - Th/Tc
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A. they are both a renewable energy
The qualifications boil down to: College education.
In most university or industrial research organizations, you might be able to work there as a member of the team who doesn't get much pay or much respect, with research going on all around you directed by other people, after you've gotten you Master's degree.
But you really don't have a shot at leading anything, or having much to say about what's being researched or how, until you have a PhD degree in the field where you'd like to do the research.
(Did I mention how proud I was to be present about 6 weeks ago, in a land far away, when my daughter was awarded a PhD degree in Molecular Biology ? I didn't want to let you get away without hearing about that.)
Answer:
D and B.
Explanation:
The wavelength must be taken from the same corresponding point. D and B are both at the crests of a wave, with no other crests in between, which means the distance between them is equal to one wavelength.
