Please help me, these are all of my points What is the first step in converting 139,000,000,000,000,000 to a scientific notation?

Count the number of positions to move the decimal place.

Drop all of the zeroes following the number 9.

Move the decimal after the number 9.

Move the decimal after the number 1.

Situation: . find the substance's half-life, in days. round your answer to the nearest tenth. a 11 gram sample of a substance that's used to treat thyroid disorders has a k. value of 0.1247. enter the correct answer n - noekt done no - initial mass (at time t = 0) n - mass at timet k a positive constant that depends on the substance itself and on the units used to measure time t= time, in days