This is a very interesting photograph. You’ve limited your colors to red, green and the color of the hand in the background. You’ve done a great job, not only on the color elements of this photograph, but also on the composition and lighting as well.
The photograph abides by the rule of thirds, uses depth to help isolate the main area of interest and has great color and object simplicity. These are many of the most important elements to have in a photograph. The result, as can be seen in your photograph, is one that produces a very professional looking photograph.
The lighting and exposure is great in this photograph. The feature that really stood out for me was the details in the texture of the hand in the background. The contrast between the dark and the light areas of the hand help draw the viewer’s eye to the area of the photograph.
You mentioned that you are not too familiar with studio lighting. As I’ve already mentioned I think your lighting is good, but if you’re concerned about the slight shadows on the left of the tomatoes you could simply use a fill light or a reflector to fill in that area and remove those shadows.
You can see an example of three point lighting here. What you are looking for is the “fill light” to help reduce the amount of shadow on the side of the tomatoes.
http://www.mediacollege.com/lighting/three-point/
I hope this helps!
I look forward to seeing your next assignment.