4. (a) Starch-degrading enzyme powder containing 5mg protein was added to a 10ml starch solution (4\%). As a result of the experiment, glucose was produced at an initial rate of 6mM/h. Find the amount (U) and specific activity of enzymes in this powder, respectively. (10 points) (b) When a substance (/) was added to the above enzyme reaction, the reaction rate decreased as follows. [5] When =Km and 3==3K, what is the degree of inhibition (i)? At this time, the definition of the low sea level is as follows. ( 10 points) i(%)=[1speedinthepresenceofaninhibitorSpeedintheabsenceof]100