What is 5.7 subtracted by 4.2?

Simplify the expression. enter the correct answer.

Aboat costs 19200 and decreases in value by 12% per year. how much will it cost in 5 years

A33 gram sample of a substance that's used to detect explosives has a k-value of 0.1473. n = noekt no = initial mass (at time t = 0) n = mass at time t k = a positive constant that depends on the substance itself and on the units used to measure time t = time, in days