If you could measure the speed at with which a galaxy rotate, what property of a galaxy could you estimate?

Which diagram shows the correct way to represent an ionic compound of magnesium oxide?

Kp is the equilibrium constant for dissociation of the propionic acid dimer. what is the sign of the slope for a plot of the natural logarithm of kp vs. inverse temperature for this reaction?

How many liters of water can be produced from 5.0liters of butane gas at stp, assuming excess oxygen? c4h10(g) + 02(g) → co2 (e) + h2o (g)