However, nothing has ever equalled the ________ and speed with which the human species is altering the physical and chemical world and demolishing the environment.
句意： 然而， 没有什么能比得上人类物种改变物理和化学世界和破坏环境的量级、 规模和速度。
magnitude大小； 量级。 concern忧虑； 担心。 determination决心； 果断。 carelessness粗心大意。