The answer is B) They do NOT require a medium to travel.
Answer:
5s
Explanation:
-A period is the time it takes to make one full back-and-forth swing.
-A period is calculated as the time taken for a complete swing divided by one cycle:

Hence, the period of the pendulum is 5s
1) 2 kilograms converted into grams is 2000
2) 5200 meters converted into kilometers is 5.2
3) 20 centimeters converted into meters is 0.2
Answer:
Oppositely charged particles attract each other, while like particles repel one another. Electrons are kept in the orbit around the nucleus by the electromagnetic force, because the nucleus in the center of the atom is positively charged and attracts the negatively charged electrons.
Explanation: