$39-$ The following query will increase

with avg$\_$salary as $($select avg$($salary$)$ from employee$)$

update employee set salary $=$ case

when salary $>{0\mathrm{.}75}^{**}$ avg$\_$salary then salary $*1\mathrm{.}15$

when salary $<mn\; id="EditorElement\_989565">0</mn><mn\; id="EditorElement\_989566">.</mn><mn\; id="EditorElement\_989567">2</mn><mn\; id="EditorElement\_989568">5</mn><mi\; id="EditorElement\_989570">*</mi><mi\; id="EditorElement\_989572">*</mi>$ avg$\_$salary then salary $*1\mathrm{.}05$

else salary $*1\mathrm{.}00$

end;

a$)$ all salaries by $15\%$

b$)$ all salaries by $5\%$

c$)$ salaries at the bottom by $15\%,$ the ones at the top by $5\%.$

d$)$ salaries at the top by $15\%,$ the ones at the bottom by $5\%$

e$)$ salaries at the top by $15\%,$ the ones at the bottom by $5\%$ and all others by $1.$

$40-$ The following query will delete

with avg$\_$sal as $($select avg$($salary$)$ from employee$)$

delete from employee where id in $($select

employee.id from

$(($employee join department on employee.dep $=$

department.id