Answer:
false is the answer because it was around in the 1880's
Explanation:
I hope this helped
Answer:
For number 2 "What do living things need to survive" you could say Food, air, water. I can't think of much more but I believe it's what any basic living thing needs. Also for number 3 all the way on the bottom you can say " A species is classified based on the popularity or kind of living thing, or where it originates from like how there's different types of birds. They all come from the same first species but evolve/change genes differently over time." hope this somewhat helped :)
The correct answer is
<span>C) -10.7 m/s
In fact, the first rock is moving upward with velocity +4.5 m/s, while the second rock is moving downward with velocity -6.2 m/s, with respect to a fixed reference frame. In the reference frame of the first rock, instead, the second rock is moving with velocity equal to its velocity in the fixed frame minus the velocity of the reference frame of the first rock:
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B. New homes
This is because in community redevelopment programs, the focus is on rebuilding and reconstruction of damaged or unused properties.
alright stay thicc and enjoy
Answer:
e_12=1-Tc/Th
This is same as the original Carnot engine.
Explanation:
For original Carnot engine, its efficiency is given by
e = 1-Tc/Th
For the composite engine, its efficiency is given by
e_12=(W_1+W_2)/Q_H1
where Q_H1 is the heat input to the first engine, W_1 s the work done by the first engine and W_2 is the work done by the second engine.
But the work done can be written as
W= Q_H + Q_C with Q_H as the heat input and Q_C as the heat emitted to the cold reservoir. So.
e_12=(Q_H1+Q_C1+Q_H2+Q_C2)/Q_H1
But Q_H2 = -Q_C1 so the second and third terms in the numerator cancel
each other.
e_12=1+Q_C2/Q_H1
but, Q_C2/Q_H2= -T_C/T'
⇒ Q_C2 = -Q_H2(T_C/T')
= Q_C1(T_C/T')
(T1 is the intermediate temperature)
But, Q_C1 = -Q_H1(T'/T_H)
so, Q_C2 = -Q_H1(T'/T_H)(T_C/T') = Q_H1(T_C/T_H) So the efficiency of the composite engine is given by
e_12=1-Tc/Th
This is same as the original Carnot engine.
