Answer:

Step-by-step explanation:
The half life is the amount of time it takes a substance to decay to half of its original amount.
Since the radioactive substance has a half life of 1000 years, there will be half of it left after 1000 years.
So, the fraction that will be left after 1000 years is 
BG = 40. Equation: 4(3) + 8 + 20 = 40.
How many elements are in the intersection of the set 1,4,7,10,...,61 and the set 1,6,11,16,...,61
LekaFEV [45]
Gggggggggggggggggggggggggggggggggggggggggggggggggggggggggggggggggggg