A single grain of sand occupies a volume of about 0.004 cubic millimeters. Based on your previous answer,

how many grains of sand are on Earth's beaches?

What is the number of moles in 15.0 g ash3?

Hot air balloons float in the air because of the difference in density between cold and hot air. in this problem, you will estimate the minimum temperature the gas inside the balloon needs to be, for it to take off. to do this, use the following variables and make these assumptions: the combined weight of the pilot basket together with that of the balloon fabric and other equipment is w. the volume of the hot air inside the balloon when it is inflated is v. the absolute temperature of the hot air at the bottom of the balloon is th (where th> tc). the absolute temperature of the cold air outside the balloon is tc and its density is ďc. the balloon is open at the bottom, so that the pressure inside and outside the balloon is the same. as always, treat air as an ideal gas. use g for the magnitude of the acceleration due to gravity.

Which of the following statements concerning the influence of culture on ethnic identity formation is accurate? a. one will reject ethnic identity if cultural stereotypes are encountered. b. if one’s ethnic city is different from the dominant cultural group, then one’s ethnic identity you will become weekend. c. if an the ethnic group is excepted by dominant culture, then ethnic identity formation can be a difficult process. d. similarity to the dominant culture can determine how easy it is for one to except ethnic differences.