Which of the following atoms is expected to have two unpaired electrons?  Al
Mg
Na
None of the above​

The rules of engagement (roe) working group is often used to (select all that apply.)

What method(s) do plants use to obtain nitrogen? select all that apply. absorb it from the atmosphere use bacteria to convert nitrogen to usable form obtain usable nitrogen compounds from the soil absorb nitrogen from water taken in at the roots

Define a is a tiny pavket of energy