The aswer would be B because you have to divide a couple numbers to get 20in.
The sum of 12 and a number
(12 + n)
is no greater
< =
then the sum of twice the number and 8
(2n +(-8)) = (2n - 8)
so we have :
(12 + n) < = (2n - 8)
Answer:
its c ! just took the test :)
Answer:
Step-by-step explanation:
For a first order decay, fraction remaining = 0.5n where n = number of half lives elapsed.
fraction remaining = 55% = 0.55
0.55 = 0.5n
log 0.55 = n log 0.5
-0.2596 = -0.301 n
n = 0.8625 = # of half lives elapsed
0.8625 half lives x 2.5 billion years/half live = 2.16 billion years have elapsed = age of the rock
b) 0.15 = 0.5n
log 0.15 = n log 0.5
-0.824 = -0.301 n
n = 2.74 half lives
2.5 billion years/half life x 2.74 half lives = 6.85 billion years = age of rock
Answer:
1/15
Step-by-step explanation: