You must be joking!
About 478,567,990.765 cubic miles
14,300 pounds. Sand has a density of 100 pounds per cubic foot.
0ne half cubic foot. One cubic foot is 100 pounds
Dry sand has a density of 100 pounds/cubic foot 1 ton = 2000 pounds 2000 pounds / 100 pounds/cubic foot = 20 cubic foot 20 cubic foot / 27 = 0.74 cubic yard So 1 ton is about 3/4 of a cubic yard
It depends on the height!
I'll use the density of dry, packed sand, which is 100 lbs per cubic foot, 50/100 is 2 50 lb bags of sand
1 cubic foot=100 lbs of sand 1728 cubic in.=100 lbs of sand 864 cubic in.= 50 lbs of sand 432 cubic in.= 25 lbs of sand and so on and so on
At 12 inch per foot that is 3.14x30x30*2/12/4 = 117.75 cubic feet of sand at 100 pounds per cubic foot = 11,775 pounds (5.88 tons). Since a yard is 27 cubic feet that is 117.75/27 = 4.4 yards
An area 10 foot x 10 foot is 100 square feet. 100 cubic feet of sand would cover it with a one foot deep layer of sand. If the sand needs to be 6 inches deep, then 50 cubic feet are be needed, or 25 cubic feet if the sand is to be 3 inches thick.
Your patio is (8x8)/6in = 10.66 cubic foot. The sand comes in 50 lb bags that cover 0.5 cubic foot so you will need 21.33 bags (round up to 22 or down to 21)
Please note that there are different kinds of sand. A table on the site "Engineeringtoolbox" lists densities between about 80 and 125 pounds per cubic foot, depending on the type of sand, and on whether it is dry or wet.
This is a tough one. First you have to decide which type of sand is 'sand'. Sand comes in many different grain sizes and in many different densities. If you have defined your sand, take a known volume, weigh it and do the math!