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.
<span>The best answer is (d) water from snowmelts. The American Southwest has many mountains that catch moist air moving westward (from the Pacific) that falls as snow during the winter. The snow melts gradually during the spring and summer when there is little precipitation. The melted snow runs off the mountains into rivers and streams that can be tapped by irrigation pumps. The snowmelt also sinks into the ground, replenishing underground aquifers that can be tapped by wells in the valleys where farming takes place.</span>
Answer:
B.
I could wrong that because there many theory.
I choose B that because my feelings think B make any sense?
Boers treated native Americans with social dominance and violence <span>during their residency in the southern part of Africa. The correct option among all the options that are given in the question is the third option or option "C". I hope that this is the answer that has come to your desired help.</span>
