Answer:
120 grams will be left after 180 years.
Step-by-step explanation:
A radioactive half-life refers to the amount of time it takes for half of the original isotope to decay and its given by
where,
= quantity of the substance remaining
= initial quantity of the substance
= time elapsed
= half life of the substance
From the information given we know that:
- The initial quantity is 480 g,
- The half-life is 90 years,
- 180 years is the time elapsed.
And we want to find how much will be left. For this we use the above formula.
120 grams will be left after 180 years.
I think you mean how many thousands equal 20 hundreds. Well it's simple, 20 hundreds equal 20*100 which equals 2,000. Therefore, 20 hundreds equals 2 thousands.
Answer:
Step-by-step explanation:
circumference = 2* pi * radius = 1
-> radius = 0.1592 mile
-
> diameter = 2* radius = 0.31847 mile
So, when we're tasked with things like this, rewriting everything in terms of sine and cosine and combining fractions often trivializes things, so doing just that gives us:
So out expression is 1/cos(x).
Step-by-step explanation:
if b+c=0
b=-c
x^b=x^-c
so
1/[2(x^b)+1]
