Situation:

a 39 gram sample of a substance that's a by-product of fireworks has a k-value of 0.1024.

n = n0e -kt

n0 = 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
find the substance's half-life, in days.

round your answer to the nearest tenth.