please solve quickly

3 (20 points,each 5 points)Assume that the following functional dependency set F={A>B,BC>D,B>E} for a relation schema R=(A,B,C,D,E). (1)Please compute AC+,B+. (2) if AC+=ABCDE and AD+=ABDE, What is the candidate key for the relation R,AC or AD ? Please give the reason. (3)What Normal Form is the relation? Please give the reason for the conclusion. (4) Please decompose the relation into two relations R1(ABC), R2(BCDE), is it a lossless join composition