2 questions

Is it possible to make use a formula to find a certain type of data

EG i have a massive list but im looking for a number that is closest to 1.7400

the list ranges from 0.000 up to 2.0121 all the way back down to 0.000
now all the numbers from 0.000 to 2.0121 are exactly the same to 2.0121 to 0.000

The closest is 1.7425 now i need a formula to do this because some data will change so i need a general formula.

The numbers Before and after it are 1.7362, 1.7394, 1.7425 (witch is the one i need), 1.7456, 1.7488
My second question is in the same list i need a formula that can highlight that row. Is this possible?