Freedmen's Bureau.............................
Indus Valley Civilization
So I actually have a Social Studies book from my old school, lucky for you, we got to the Cold War.
Here's what the book stated:
One of Reagan's proposals was the Strategic Defense Initiative (SDI). He believed this defense shield could make nuclear war impossible, but the unlikelihood that the technology could ever work led opponents to dub SDI "Star Wars."
Also, I do know that this is also found on another website but thats probably where the book's information came from.
Explanation:
part A
we know how much erg of radiant energy the sun produces for one second so to find out how much it produces for 2.45 ⋅ 10^5 seconds we only should multiply these seconds to the erg of radiant energy it produces for one second
amd we get 9.555*10^38erg of radiant energy
Part B:
0.0074mm knowing that blood cell is very small to be seen normally without microscope.
and 7400mm is a measure that is quite big for a blood cell. So it remains that 7.4*10^-3 is the right one.
The answer is D. HPV because there are no cures for it but many of the small infections go away on their own.