B
When frequency increases, as does the energy, but wavelength decreases. It also works vise versa; if wavelength were to increase, its frequency and energy will decrease.
He paid 2 dollars for each bag. Then add 15 cents for that and he would charge $2.15 for each bag.
<span> N-16
</span>7 protons & 9 neutrons
<span>7 + 9 = 16
</span>
Radium and polonium is the answer to this question. I hope I helped out!