Potassium (K) is in Group I of the periodic table, and elements in the same column (period) are similar. Sodium (Na), or lithium (Li) are similar.
The right answer is 2.
The number of protons contained in a nucleus (called an atomic number) is characteristic of a chemical element. For a given atomic number, the number of neutrons defines different "types" of this element: isotopes. The variation of the number of protons of the nucleus of an atom, during a nuclear reaction for example, causes a change of the element studied.
Answer:
The United States leads the world with over 260 billion short tons of recoverable coal reserves—28% of total global reserves and 50% more than Russia, which possesses the world's second largest reserves. so the answer would be 28%
Explanation: