when an optical telescope located on the ground is used to view the sky the image has to surpass through the earth's atmosphere which is polluted. so the resolution wont be clear. When viewed on a mountain top both optical and infrared telescopes would perform better as the air above the atmosphere is less depth and cleaner.
If you mean the industrialized apple juice then yes. Even though there are several different compounds and some of them aren't actually dissolved in the liquid, since you can't actually distinguish between them using only your eyes and they do no separate naturally it is actually a homogeneous mixture.