The correct answer would be that they have more MASS per volume than air.
There is 1 aluminium atom and 4 polonium atoms
One way that I would really describe these kind of mirrors would be like first, these kind of mirrors are for sure <span>virtual, upright, smaller. And this would be only due mainly because this the kind of mirror this would be. So based from my information. So based from your options, the answer would most likely be one of the options that would practically fit this. This would be known to be "</span><span> upright and smaller than object".</span>
I'm not sure but I think it is C. CrO3
