Answer:
D.
They have a positive charge and are present in the nucleus of an atom along with the neutrons.
explanation:
Protons have a positive charge.
<em>m Na₂CO₃: 23g×2 + 12g + 16g×3 = 106 g/mol</em>
------------------------------
1 mol ------- 106g
X ------------ 10,6g
X = 10,6/106
<u>X = 0,1 mol Na₂CO₃</u>
The answer is low frequency and long wavelength