Answer:
the final temperature = 74.33°C
Explanation:
Using the expression Q = mcΔT for the heat transfer and the change in temperature .
Here ;
Q = heat transfer
m = mass of substance
c = specific heat
ΔT = the change in temperature
The heat Q required to change the phase of a sample mass m is:
Q = m
where;
is the latent heat of vaporization.
From the question ;
Let M represent the mass of the coffee that remains after evaporation is:
ΔT = 
where;
m = 2.50 g
M = (240 - 2.50) g = 237.5 g
= 539 kcal/kg
c = 1.00kcal/kg. °C
ΔT = 
ΔT = 5.67°C
The final temperature of the coffee is:
ΔT
where ;
= initial temperature = 80 °C
= (80 - 5.67)°C
= 74.33°C
Thus; the final temperature = 74.33°C
I believe it’s “C”
Hope that’s help you(:
Explanation:
velocity is distance divided by time.
so
the average speed of the ball is 10m/20s
= 0.5 m/s
If the earth's mass were half its actual value but its radius stayed the same, the escape velocity of the earth would be 
.
<h3>What is an escape velocity?</h3>
The ratio of the object's travel distance over a specific period of time is known as its velocity. As a vector quantity, the velocity requires both the magnitude and the direction. the slowest possible speed at which a body can break out of the gravitational pull of a certain planet or another object.
The formula to calculate the escape velocity of earth is given below:-
Given that earth's mass was half its actual value but its radius stayed the same. The escape velocity will be calculated as below:-
.
Therefore, If the earth's mass were half its actual value but its radius stayed the same, the escape velocity of the earth would be .
To know more about escape velocity follow
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