We saw that

 100.5 (decimal) = 1.1001001 (binary) * 26
   

So

    E is 6 = 0000 0110
so  e = E + bias

                1111 11
           E:   0000 0110
        bias:   0111 1111
                ---------
e = E + bias:   1000 0101

Since 100.5 is positive

 s = 0      
   

What is f?