An isotope is one of the forms of an element that has the same number of protons, but a different number of neutrons.
Answer:
1.7% is stored in the polar icecaps, glaciers, and permanent snow
Explanation:
70% of the Earth's surface is covered with water; However, only a small percentage, 0.025%, is suitable for human consumption. A limited resource whose demand, according to the forecasts of the Organization for Economic Cooperation and Development (OECD), will skyrocket up to 55% globally between 2000 and 2050.
In the attached infographic we observe that the total volume of water on Earth is 1,386 million cubic kilometers, of which<em> </em><u>1.7% is forming polar ice, cap glaciers and permanent snow</u>. 1,338 million cubic kilometers of that water is in seas and oceans, that is, 96.5% is in seas and oceans, that is, it is salt water that cannot be drunk.
Only 3.5% of the Earth's water is fresh, but of this percentage, only 1% of the Earth's fresh water flows through the river basins in the form of streams and rivers.
(a) 1200 rad/s
The angular acceleration of the rotor is given by:

where we have
is the angular acceleration (negative since the rotor is slowing down)
is the final angular speed
is the initial angular speed
t = 10.0 s is the time interval
Solving for
, we find the final angular speed after 10.0 s:

(b) 25 s
We can calculate the time needed for the rotor to come to rest, by using again the same formula:

If we re-arrange it for t, we get:

where here we have
is the initial angular speed
is the final angular speed
is the angular acceleration
Solving the equation,

Answer:
Maybe A is the correct answer