Answer:
1. NaCl - 2 atoms
2. K2O - 3 atoms
3. AgH - 2 atoms
Step-by-step explanation:
NaCl is composed of 1 atom of Na (Sodium) and 1 of Cl (Chlorine)
K2O is composed of 2 atoms of K (Potassium) and 1 of O (Oxygen)
AgH is composed of 1 atom of Ag (Silver) and 1 of H (Hydrogen)