There are many different types of scientific investigations.  which of the following forms requires the identification and control of variables?

Agas initially at p1 = 1 bar and occupying a volume of 0.5 liter is compressed within a piston–cylinder assembly to a final pressure p2 = 4 bar. (a) if the relationship between pressure and volume during the compression is pv = constant, determine the volume, in liters, at a pressure of 3 bar. (b) repeat for a linear pressure–volume relationship between the same end states. reference

Which changes would result in a decrease in the gravitational force btween two objects? check all that apply

Due in 40 explain in terms of frame of reference if you’re inside a moving train everything on the outside can seem to be moving