Question on values in "slashing" section of genesis

Hi. I am trying to better understand the values in the slashing module. In genesis, I see the following values as params:

“signed_blocks_window”: “100”,
“min_signed_per_window”: “0.500000000000000000”,
“downtime_jail_duration”: “600000000000”,
“slash_fraction_double_sign”: “0.050000000000000000”,
“slash_fraction_downtime”: “0.010000000000000000”

Is there a reference that explains what these mean and their units?

I understand that signed_blocks_window is the sliding window of # of blocks within which I need to meet the min_signed_per_window ratio of blocks voted on. So in the above example, if I fail to vote on 50% or more of the blocks in a 100 block sliding window, I will get slashed and jailed.

What is the jail duration in? nanoseconds makes sense as that would mean 10 minutes here. Otherwise, if microseconds, it is 10,000 mins.

What about the slash fractions? So if I am down, do I get slashed by slash_fraction_downtime every block that I am not meeting the min_signed_per_window ratio? Or do I get slashed once and then all the “counters” get reset? Is that fraction a percentage then, where 0.01 for downtime means 1% of my stake?

What about the two following values? What do they mean?

“signing_infos”: {},
“missed_blocks”: {}

Thanks so very much.