The correct answer is C. i think
Answer:
B or C
Step-by-step explanation:
if its refering to the answer of 11 × X then the answer is C, but if its not the answer might be B.
<span>As the age of the U-235 sample is 2.631 billion years, and the half-life of U-235 is 713 million years, the sample has undergone 2.361 X 1,000,000,000 / 713 X 1,000,000 = 3.69 half lives. In each half-life the sample reduces to half its original weight according to the radioactive Half-Life Formula:
ln (Nt /N0) = -kt, where N0 = mass of the original weight of radioactive material, Nt = mass of radioactive material at time t, k = decay constant and t = time interval . We have to put Nt/N0 = 1/2 for time interval = half-life.</span>
Step-by-step explanation:
I am not allowed to answer more than 3 questions. So I will do the first 3.
15a. i) (2/3) = 4/9
ii) (2/3) = 8/27
iii) (2/3) = 16/81
b. The product is small because you are finding the fraction of a fraction.
16. Compared to the factors, the product is less than each fraction. This is because, as stated above, you are trying to find a fraction (a part of the whole) of another fraction. When you multiply a whole number by a fraction, the whole number decreases. The same applies to a fraction.
17a. 0.4 × 0.3 = 0.12
b. 0.4 = 4/10 = 2/5
0.3 = 3/10
3/10 × 2/5 = 6/50
