I got 114688 by going up x4
The amount of substance left of a radioactive element of half life,
after a time, t, is given by:
Given that <span>potassium-40 has a half life of approximately 1.25 billion
years.
The number of years it will take for 0.1% of potassium-40 to remain is obtained as follows:
Therefore, </span><span>the maximum age of a fossil that we could date using 40k is
12.5 billion years.</span>
Answer:
c)
Step-by-step explanation:
Equation for regression line of y on x is given as
where
= predicted value
m = slope of line
b = intercept
m and b are found as
r = correlation coefficient = 0.88
Sx = standard deviation for independent variable x = 13
Sy = standard deviation for dependent variable y = 27
= mean value of independent variable x = 21
= mean value of dependent variable y = 55
Substituting these values in (2) and (3)
Putting these values of m and b in (1)
It CAN'T equal 21, since 9+10=19
BUT, if the 9 was changed to like, 11 - Then it would = 21, or if the 10 was changed to a 12, it would make 21 also,
Answer:
Step 1: Make sure the bottom numbers (the denominators) are the same
Step 2: Add the top numbers (the numerators), put that answer over the denominator
Step 3: Simplify the fraction (if needed)
Step-by-step explanation: