Need Relational algebra for below schema

Relational Schema:

Classes(class, type, country, numGuns, bore, displacement)

Ships(name, class, launched)

Battles(name, date)

Outcomes(ship, battle, result)

a) List the name, displacement, and number of guns of the ships engaged in the battle of Guadalcanal.

b) List all the ships mentioned in the database. (Remember that all these ships may not appear in the Ships relation.)

d) Find those countries that have both battleships (bb) and battlecruisers (bc).

e)Find those ships that "lived to fight another day"; they were damaged in one battle and later fought in another. (hint: join outcomes with battles, for the date, and then work with that intermediate result)