MIPS questions

In an instruction, how many bits need to be examined to determine the format of an instruction? All 32 bits The first 6 bits The first hex digit The last 16 bits The following instruction is to be assembled and converted to binary target Assume that the current PC is 0x00400010 (after the increment) and the target label has the value of 0x00400080. What is the binary value of the constant in the instruction? 0000 0000 0111 0000 00 0001 0000 0000 0000 0010 0000 0000 0000 0001 1100 00 0100 0000 0000 0000 1000 0000 What is the following instruction? 0x00128882 srl 4 bits srl 2 bits sll 2 bits sll 4 bits