The amount of a radioactive material has been reduced to 24 percent of the original value. If the half-life is 6230 years, the age of the sample is estimated to be :a) 6160 years b) 19100 years c) 8890 years d) 12800 years e) 25700 years

d) 12800 years.

Step-by-step explanation:

The equation for the decay of radioactive material has the following form:

Where is the time constant.

There is a relation between half-life and time constant:

The estimated age of the sample is isolated from the decay equation:

The correct answer is D.  

the answer is 96 degrees

step-by-step explanation:

you have to realize that a line equals 180 degrees

guess at question:

a vertical line intersects the graph of g(x,y) = 0 at two points. what conclusion follows about the function f(x) implicitly defined by g(x,f(x)) = 0?

the domain of f(x) cannot include the x coordinate of any such vertical line.

informally, f(x) is not a function, and

g(x,y)=0 cannot be solved for y uniquely.

the relation r = {(x,y) such that g(x,y) = 0} is a function if

for all (a,b) ∊ r and (c,d) ∊ r, a=c implies b=d.

step-by-step explanation: