I’m really bad at math and really don’t get it so can someone please help for 20 points

What is the value with a place of tenths in 907.456 1) 0 2) 6 3) 4 4) 5

If you can solve all of these i will give ! - 4% of 190 - 4% of 162.5 - 4% of 140 - a 4% increase from 155.1 - a 4% increase from 159.8

Awater holding tank measures 105 m long, 50 m wide, and 8 m deep. traces of mercury have been found in the tank, with a concen- tration of 60 mg/l. what is the total mass of mercury in the tank? answer in units of kg.