Find the length of string and speed of wave in string

[myoplex11]

Homework Statement

Find the length of string and speed of wave in string if frequency of given wave is 850 hz and the wavelength is 0.173m? The string is in a tube that is closed at both ends.

Homework Equations

v=(T/(m/L)^.5

The Attempt at a Solution

I found the speed using v=frequency*wavelength.
How do i find the length of the string?
i don't know the mass or the tension

 

[Shooting Star]

The Attempt at a Solution

I found the speed using v=frequency*wavelength.
How do i find the length of the string?
i don't know the mass or the tension

This is a standing wave. Have you read about that?

Assume that the frequency given is that of the fundamental. What is the relationship between the wavelength and the length? In this case, the ends of the string are both nodes.