Tension and Fundamental frequency

[Big-Daddy]

The fundamental frequency of a uniform wire with an AC current of constant magnitude was found at various different tensions and a graph of (T^1/2,l) was plotted (l was the length between the two nodes of the wire when the fundamental frequency was found). How would the data on the graph (including gradient) be affected by a) using a wire of smaller diameter, b) increasing the current or c) using a DC current of the same constant magnitude?

I've already written down how far I got (in terms of the experiment which I set up and decided to plot with that graph) but I really don't know how to start with this question. I know that c), using a DC current would yield no results of fundamental frequency as no standing wave is formed at all. Any help appreciated :)

 

[rude man]

I think if you expect any responses you might have to describe the experiment more fully.