It's a 4 mark question, what do I do??​

Select the correct answer from each drop-down menu. daniel and sanya are scientists. daniel is studying whether the increasing frequency of tropical storms is affecting coastal erosion. sanya is investigating whether the discharge from industrial plants has any impact on the ph concentration of freshwater swamps in the surrounding area. which fields of science are daniel’s and sanya’s studies most closely related to? daniel’s field of study is related to science, and sanya’s field of study is related to .

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 description best characterizes the motion of particles in a solid?