I think she wants us to use bits 7-51 of some SHA hash.
.. or bytes 7-51, but this is a bit unlikely. You can not predict the result of the SHA function, it would be like using the random numbers.
Other question is which exact of the many SHA functions?
She wouldn't have to predict the hash. She could use any string for that password. She doesn't have to know it in advance.
Which SHA function? I'd assume 1 (the first commonly referred to as "SHA") or 2 (the 256 bit variety used by Bitcoin).
If there's a weakness to my theory, I think it's that 45 bits doesn't give much brute force resistance.