In the metric system, you give a name to the following multiples: 10, 100, 1000, 0.1, 0.01, 0.001, and then you skip three places. So, you have

And thus 0.000001 of something is a micro-something (i.e. one millionth of a certain unit)
2/cos x
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Not sure what you’re trying to find but here’s the simplified version:
-4<=2t+5<11
-9<=2t<6
-9/2<=t<3
8 39/40
=8+39/40
=8•40/40+39/40
=320/40+39/40
=320+39/40
=359/40
=8.975
The answer is 8 39/40=8.975