There is a block of addresses 218.94.21.0/24. 
Please denote the block of addresses in binary system. 
Please create four subnets (of form a.b.c.d/x) from the addresses at the same size.   the four subnet are (          )、(       )、(     )and (         ).   please use the form of a.b.c.d/x, such as 218.94.21.0/24 for each blank.
What is the range of host id for  the sub-network  218.94.21.64/26?