<span>Water in the oceans may become fresh water available to humans through the processes of evaporation, condensation and precipitation.
In these processes, water is heated to a very high temperature until it evaporates in order to kill the germs and remove the salts which remains after water evaporation. The next step in condensing the water vapor (which is now fresh) and precipitating this vapor to be used by humans.</span>
Answer:

Explanation:
We are given that
Gravitational force=
r=0,U(0)=0
We know that
Gravitational potential energy=


Substitute r=0 ,U(0)=0


Substitute the value

Answer:

Explanation:
From the question we are told that
Weight of fireman 
Pole distance 
Final speed is 
Generally the equation for velocity is mathematically represented as

Therefore Acceleration a
Generally the equation for Frictional force
is mathematically given as



Therefore

These are characteristics of a wave. The amplitude is how high and low the waves go. Crests are high points on the wave, and troughs are low points on the wave.
Let v = the running speed
After running at constant speed for 26 min, the distance traveled is
d = (v m/min)*(26 min) = 26v m
Because there are 1500 m to go, the distance traveled is
10000 - 1500 = 8500 m
The running speed is
v = (8500 m)/(26 min) = 326.9 m/min
In km/h, the speed is
v = (0.3269 km/min)*(60 min/h) = 19.6 km/h
Answer: The running speed is 19.6 km/h