Could someone help me in next:

In what way should next values be formatted?

1.0001 -> x?
1.0091 -> x? (rounding up/down/none?)
-0.00001 -> x? ("0" or "-0.00" or..)

Or may i output as many digits as i can, but at most 2 of fraction should exactly match?

i just rounded values:
1.0001 -> 1.00
1.0091 -> 1.01
-0.00001 -> -0.00
and got AC.