so the question is : List three different factors which influence the rate of enzyme activity and specifically explain each factor’s influence on enzyme activity.

My answer:
Since enzymes are proteins, they are very sensitive to environmental conditions. The very nature of large 3-dimensional structure of the protein makes it prone to changes in temperature, pH, chemicals, etc. These changes can easily cause a change in the 3-d shape of the protein called denaturation. Obviously, if the shape of the enzyme changes, (i.e. it has been denatured) then the shape of the active site changes. If the shape of the active site changes, the substrate will no longer fit and the enzyme becomes nonfunctional. Enzymes which function in the human body work optimally within a temperature range of 35 to 39ºC and a pH range very specific to their location. An enzyme which functions in the stomach would function best at pH 2, in the small intestine at a pH of 9, or in the cell cytoplasm at a pH of 7.3 to 7.4. An enzyme which normally functions in the stomach will not function in the small intestine.

Is this good? like do I need to add more things?

Frankly, you ignored my last response. Let me repeat some: THe three most important factors are pH, temperature, and concentration of substrate and enzyme. You should not ignore concentration. I don't think I would even mention denaturation...why would anyone be interested in rate of enzyme active on destroyed (denatured) proteins? To me, the question is asking what affects enzyme rate on proteins, and that is pH, temp, and concentration.

I am not certain I agree with your statement on the optimal temperatures, they are much more selective than a 4C range. Some can shut off at +- 0.5C.
On the pH ranges you give, it depends on the enzyme, you generalized (An enzyme which functions in the stomach) and I would NOT do that. Pepsin is optimal at pH2, if you are thinking on pepsin, then say pepsin is optimal at pH 2. The same comment applies to the other locations: specify the enzyme, and its optimal range. THe last statement ...An enzyme which normally functions in the stomach will not function in the small intestine...Really? You are generalizing again. There are a series of microbial enzymes that will work no starches in a broad pH range of 3 to 8. In the upper part of the stomach, the pH is about 5, and many stomach enzymes work in that region as well as in the lower intestinal tract.
So, I recommend you discuss
1) concentration of enzyme, and of substrate on rate of reaction, and
2) get specific on temps and pH by giving specific examples, not generalizing. When one generalizes, one is seldom on target.

http://en.wikipedia.org/wiki/Rate_of_enzyme_mediated_reactions

http://www.worthington-biochem.com/introBiochem/introEnzymes.html