<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>
19x - 22 is you combine like terms!
All you do is multiply 22 times 8 which is 176 then you multiply 8*4
A,B,C,D,E i THINK so because if you are 6 units away then the cordinets have to have six in it im not sure tho if X axis than A,B,C
