I hate math bro please help me

Blank × 10-3 is 2,000 times greater than 1.9 × 10-6. it is also blank times greater than 9.5 × 10-4.

Aswimming pool had 2.5 million liters of water in it. some water evaporated, and then the pool only had 22 million liters of water in it. what percent of the water evaporated?

Can someone me with #s 8, 9, and 11. with just one of the three also works. prove using only trig identities.