It will be something like b or d
Metal, metal, nonmetal, metal, nonmetal, nonmetal. For the covalent bonds, it's always between nonmetals. For the ionic, it's a metal and a nonmetal. Hope this helps!
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.
Answer:
How do people survive in Antarctica in the winter? Mainly by staying on the station. By not leaving at all during the permanent night, by not travelling for too far and by staying put in a tent or hut if caught out in a blizzard rather than trying to go back to the station.
Explanation:
