Mass = no. of moles x molecular weight
m = n x Mr
m = 2.5 mol x (24 + [16 x 2])
m = 140g
A rock has 12.5 percent of its original amount of potassium-40 remaining in it; potassium-40 has a half-life of 1.25 billion years. <span>3.75 billion years ago</span> was the <span>rock formed. the answer is letter C</span>
If you meant to say 100C, then yes this is True.
Well since i need points I am going to say read the text