Answer:
three half-lives
Explanation:
Converting 12.5% to decimal gives 0.125
If one half life is 0.5.
0.5*0.5*0.5 gives 0.125
Thus 3-half lives has been elapsed
Western Union has been around over a hundred years, even though it wasn´t named like that before and its main business was connecting people across the United States and overseas through telegraph, its main activity until 1879 when telephone replaced telegraph and the company lost a sue againt BELL and decided to change its way to earn money starting offering money transferring service from and to the United States, being today one of the biggest financial service company all over the world.
The correct answer is - Watershed.
The drainage basis are places in which all the water in an area is accumulated and ends up in the same place. The drainage systems are divided by highlands, which can vary from small hills to very high mountains, depending on the topography of the place.
The line on the highland that is separating the drainage systems is called watershed. The watershed is simply a line stretching on the highest parts of a highland, thus having a slope on each side.