Q51

Consider the relation Student (name, sex, marks), where the primary key is shown underlined, pertaining to students in a class that has at least one boy and one girl. What does the following relational algebra expression produce? (Note: $\rho$ is the rename operator). $\displaystyle \pi_{name} \{\sigma_{sex=female} (\text{Student}) \} - \pi_{name} (\text{Student}\bowtie _{(sex=female \wedge x=male \wedge marks \leq m)} \rho_{n, x, m}(\text{Student}))$