Answer:
The answer to your question is: Arsenic (As)
Step-by-step explanation:
Krypton is a noble gas located in group VIII A and 4rd period. Nitrogen is in the 5fh group.
So, we must look for an element located in the 4rd period and group VA.
Iron (Fe) Iron is in the 4rd period and group VI B
Selenium (Se) Selenium is in the 4rd period and group VI A
Arsenic (As) Arsenic is in the 4rd period and group V A and group VA
Calcium (Ca) Calcium is located in group 4rd and group IIA