Answer: The black ball will have more mass than the white ball.
Explanation: Density of a substance is defined as the ratio of mass and volume occupied by the substance.
Mathematically,

We are given that the two balls are of same size, which means that the volume of both the balls are same. We are also given that the black ball is more dense than the white ball, which means that the black ball will have more mass.
As, 
It will be the second one
The average speed is 0.28
Answer:
1) No shift
2) No shift
3) Leftward shift
4)Rightward sifht
Explanation:
1) 2) Adding N or Removing N in the equilibrium will produce No shift, because of its solid state, the N is not contemplated in the equilibrium equation:
3) Increasing the volume produces a decrase in the preassure due to the expansion of the gases. This will cause a leftward shift, because the system will try to increase the moles of gas and in consecuence of this, also increase the preassure.
4) Decreasing the volume has the opposite effect of the item 3): the preassure will increase and the system will consume moles of gas to decrease it, producing a rightward shift.
Answer:
Compared to other stars we observe, the Sun appears bigger and brighter because it is much closer to earth.
Objects closer to earth appear to be much bigger and brighter.
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