Set this up as
10 = 40 (1/2)t/28
and solve for t in years.
10/40 = (1/2)t/28
log(0.25) = (t/28) log(0.5)
t = 28 log(0.25) / log(0.5) years = 56 years
Test the answer:
56 years = 2(28 years) = 2 half-lives, so the remaining amount should be 1/2 of 1/2 of the initial amount, i.e. 1/4 of the initial amount, and 10 mg = 1/4 of 40 mg.
I'm not sure, but wouldn't it be carpet weaving or sewing?
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.
Summer days are longer and winter days are shorter
Answer:
There are three types of plate boundaries. Each of them have natural disasters that they cause.
Explanation:
1. divergent boundaries- two plates are moving away form each other and magma moves up into the empty space
a. two continental plates make a rift valley; such as the east african rift valley
b. two ocean plates make rifts and ridges; such as the mid-atlantic rift
2. convergent boundaries- a direct collision of one plate with another
a. one oceanic plate and one continental plate form volcanoes; such as mount saint helens
b. two continental plates push up onto each other and make a folded mountain; such as mount everest
c. two oceanic plates form an island arc; such as japan island
3. transform boundaries two plates slide past each other creating a fault
a. not many examples of this, but san andreas fault in california is one
I hope this was helpful!!
