Answer:
Step-by-step explanation:
O Potassium and Bromine are in the same period.
The periodic table is a chart of all the known elements arranged according to their atomic structure. Elements in the same period are in the same row of the periodic table and have similar chemical properties because they have the same number of electron shells.
O Nitrogen and Bismuth are not in the same period. Nitrogen is in period 2 and bismuth is in period 6.
O Silver and Calcium are not in the same period. Silver is in period 5 and calcium is in period 4.
O Fluorine and Chlorine are in the same period. They are both in period 2.