The law of conservation of energy is a law that states that "energy cannot be created or destroyed, only changed" this means that you can't create it or destroyed as in, if you burn wood, you have released the energy. you haven't destroyed it, you have just released it
a) Answer;
= 6.72 hours
Explanation and solution;
velocity = distance over time
Since we know the velocity and the distance, we can simply calculate time
For the first part
85 km/h = 300km / time
time = 3.53 hours
Then there is a 22 min stop, which is the same as 0.37 hours
so far the trip is:
3.53 + 0.37 = 3.9 hours
then for the last stretch:
78 km/h = 220 km / time
time = 2.82 hours
So the total trip is:
3.9 + 2.82 = 6.72 hours
b) Answer;
= 77.38 km/hr
Explanation and solution;
we take the total distance divided by the total time to get the average.
total distance = 300 km + 220 km = 520 km
total time = 6.72 hours
Average velocity = 520 km / 6.72 hours = 77.38 km/hr
For a curved mirror, all points have the same normal and the angle of incidence is also equal to the angle of reflection.
According to the laws of reflection, the incident ray, reflected ray and normal all lie on the same plane. For a curved mirror, the normal remains the same at all points along the curved mirror.
Again, the angle made between the incident ray and the normal is the same as the angle made between the reflected ray and the normal. Therefore, the angle of reflection is equal to the angle of incidence.
Learn more: brainly.com/question/17638582
Answer:
Explanation:
Thus, we find 
(input rate of brine)
Since the solution is pumped out at a slower rate, thus it is accumulating
at the rate of 
Thus, after t minutes there will be 
gallons in tank
(concentration of salt in outflow) \cdot (output rate of brine)
Now, we substitute by these results in the 
to get
