Via half-life equation we have:

Where the initial amount is 50 grams, half-life is 4 minutes, and time elapsed is 12 minutes. By plugging those values in we get:

There is 6.25 grams left of Ra-229 after 12 minutes.
So,
GPE (graviational potential energy) = mass x g x height
GPE is depends on where zero height is defined. In this situation, we define h = 0 as the initial height.



The builder has gained 18.375 kJ of PE.
the answer is CaO because that's what my homework says is correct
Answer:
0.000625 V
Explanation:
The formula linking current , resistance and voltage is :
V = I/R
Voltage = Current / Resistance
Now we substitute values given in question :
Voltage = 0.250 / 400
Voltage (V) = 0.000625
Our final answer is 0.000625 V
Hope this helped and have a good day
Answer:
The answer would be 735J
Explanation:
PE=mgh
=(mass)(force of gravity)(height)
=(25kg)(9.8m/s^2)(3m)
=735J