We have direct experimental evidence (from large particle accelerators) for the physical conditions in the universe back to about after the big bang.
a. 3 minutes
b. 380,000 years
c. 10-10 seconds
d.1 million years
e. 300 years

c. 10-10 seconds

Explanation:

To be able to penetrate very deeply into the matter we need to generate very high energies, we need somehow very energetic particles that can test very small distances inside the matter. And for that you have to build particle accelerators. For example, a proton is a constituent of the atom, the nucleus of the hydrogen atom. These particles accelerate in an accelerator until they reach speeds very close to the speed of light and the highest energies ever before reached by a man-made instrument on earth.

Then with these high energies we test the small distances, the deepest structure of matter and what is interesting is that by producing these enormous energies in a laboratory and in a tiny microscopic region of space we are reproducing the conditions that were present in our universe primitive. Actually in fractions of seconds after the Big Bang.

Technology is enough for us today to reach 10 ^ (- 10) seconds after the Big Bang (ie 0.0000000001 seconds).

2,407.2 miles. or 32 hours.