I believe it is the dependent variable b/c it is the thing(s) that is been observe or measure
Answer: The number 4 indicates 4 electrons.
Explanation: We are given an electronic configuration, which is:

Here,
- The letters denote the sub-shells of an element.
- The numbers written before the letters which are 1, 2 and 2 represents the Principle Quantum Number and these represents the energy level of the sub-shells.
- The number which are written in the superscripts which are 2, 2 and 4 denotes the electrons which are present in the sub-shell.
Hence, 4 indicates 4 electrons present in 2p sub-shell.
Ionic compounds are the combination of two elements, one of which is a metal, while the other is a nonmetal. The intermolecular forces binding them is called an ionic bond. To name an ionic compound, take the name of the metal element first, followed by the nonmetal, but adding the suffix -ide. For example, NaCl is named as sodium chloride.
Answer:
c) NOx and VOC
oxides of nitrogen (NOx) and volatile organic compounds (VOC)
Explanation:
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