To solve this problem it is necessary to apply the concepts related to the Stefan-Boltzmann law which establishes that a black body emits thermal radiation with a total hemispheric emissive power (W / m²) proportional to the fourth power of its temperature.
Heat flow is obtained as follows:

Where,
F =View Factor
A = Cross sectional Area
Stefan-Boltzmann constant
T= Temperature
Our values are given as
D = 0.6m

The view factor between two coaxial parallel disks would be


Then the view factor between base to top surface of the cylinder becomes
. From the summation rule


Then the net rate of radiation heat transfer from the disks to the environment is calculated as





Therefore the rate heat radiation is 780.76W
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.