Answer:
equation number 3 is balanced.
hope it helps ☺️!
Scientist typically use the international system of measurements, or the metric system. If you mean English as in England, then yes.<span> The United States' system of measurement is not usually used by scientists.</span>
Your answer would be 0.00285 moles.
We can calculate how long the decay by using the half-life equation. It is expressed as:
A = Ao e^-kt
<span>where A is the amount left at t years, Ao is the initial concentration, and k is a constant.
</span><span>From the half-life data, we can calculate for k.
</span>
1/2(Ao) = Ao e^-k(30)
<span>k = 0.023
</span>
0.04Ao = Ao e^0.023(t)
<span>t = 140 sec</span>
