Number 106 plz ! will give brainiest

Plz ! ive been stuck on this forever

The concept of keystone species is controversial among ecologists because most organisms are highly interdependent. if each of the trophic levels is dependant on all others how can we say one is most important

Asolution of an enzyme and a substrate was placed in a water bath and the temperature of the reaction was raised gradually. the graph shown was plotted at the end of the experiment. what can be concluded from the graph? a) temperature has no effect on the activity of the enzyme. b) the effect of temperature on the enzyme is unpredictable. c) the enzyme shows increased activity up to a certain temperature. d) the activity of the enzyme is inversely proportional to the temperature.