The correct answer for the question that is being presented above is this one: "Schmidt-Cassegrain focus." A focal arrangement that has a thin lens that the light passes through before traveling down the tube to the objective mirror is a Schmidt-Cassegrain focus.
Here are the following choices:
a. Cassegrain focus
b. Newtonian focus
c. Schmidt-Cassegrain focus
<span>d. Schmidt focus</span>
The radiations detected by Arno Penzias and Robert Wilson
were the original heat from the Big Bang.
Today, we call those waves the "Cosmic Microwave Background".
I'm not sure, but I think those guys were awarded a Nobel Prize in Physics
for that discovery.
A because it some type of friction