The factor (s) likely to increase the rate of reaction catalyzed

The factor (s) likely to increase the rate of reaction catalyzed by a surface immobilized enzyme is/are

1. Increased agitation of the bulk liquid containing the substrate
2. Continued replacement of the bulk liquid containing the substrate
3. Increased concentration of the substrate in the bulk liquid
4. All of these

Continuous change in the substrate concentration in bulk liquid does not allow enzyme to attain the reverse feedback condition.