Answer:
Explanation:
Let A₀ = the original amount of ⁵⁵Co
.
The amount remaining after one half-life is ½A₀.
After two half-lives, the amount remaining is ½ ×½A₀ = (½)²A₀.
After three half-lives, the amount remaining is ½ ×(½)²A₀ = (½)³A₀.
The general formula for the amount remaining is:
A =A₀(½)ⁿ
where n is the number of half-lives
n = t/t_½
Data:
A = 1.90 ng
t = 45 h
t_½ = 18.0 h
Calculation:
(a) Calculate n
n = 45/18.0 = 2.5
(b) Calculate A
1.90 = A₀ × (½)^2.5
1.90 = A₀ × 0.178
A₀ = 1.90/0.178 = 10.7 ng
The original mass of ⁵⁵Co was .
Answer:
There are a couple different types of precipitation, though it is generally taken to mean a synonym for rain. It includes rain, snow, sleet, and hail. With the increase in global warming, there is more precipitation. In general, the type of precipitation varies with the season; we see less in the summer of all types, more snow, sleet, and hail in the winter, and more rain in the temperate seasons like fall.
Answer:
Hi! your answer would be C. Plants produce oxygen through photosynthesis, and fish depend on this oxygen to survive.
Explanation:
I took the test and got this question right!
Answer:
4%
Explanation:
the answer is 4% , hope this help
