What are the 3 environmental factors affect the rate at which an enzyme works and how do they change the situation?

1) temperature -  if temperature increases, initially the rate of reaction will increase, but if the effect of bond breaking will become greater and greater, rate of reaction will begin to decrease.
2) pH value- change in pH above or below the optimum pH decrease the rate of reaction.
3) substrate concentration - increasing concentration increases the rate of reaction, more product will be make.