What is the unit for spring constant?

1.   ?    N/m
2.   ?    watts
3.   ?    joule
4.   ?    N

What is the unit for power?

1.   ?    N/m
2.   ?    watts
3.   ?    joule
4.   ?    N

What is the unit for work?

1.   ?    N/m
2.   ?    watts
3.   ?    joule
4.   ?    N