Assembly language, accessing bytes of memory
You want to use the 'lw' operation (load word) to grab 0x100 it has the format 'lw $rt SignImm($rs)'. Then you need to do an 'and' operation with the appropriate bit mask to extract the state of that bit. The and op is in the form 'and $rd, $rs, $rt'.

So say the bottom 4 bits are: 1001, and you AND that with 1000. The result will be 1000, telling you that the 4th bit is a 1.