Answer:
The 3rd one is correct
Explanation:
Protons and neutrons have approximately the same mass, about 1.67 × 10−24 grams, which scientists define as one atomic mass unit (amu) or one Dalton. Each electron has a negative charge (−1) equal to the positive charge of a proton (+1). Neutrons are uncharged particles found within the nucleus.
Be 1s²2s², [He]2s²
beryllium (2- second period, s² - 2A group)
Answer:
digital signal is the answer
Answer:
Explanation:What is the demand factor for three commercial ranges?
