________ is a commonly used scripting language for creating DHTML effects

What is the display stack?

What will be an ideal response?

Provide the equivalent domain relational calculus and relational algebra expressions for each of the tuple relational calculus expressions given in Exercise 4.10.

(a) {H.hotelName | Hotel(H) ? H.city = ‘London’} (b) {H.hotelName | Hotel(H) ? (?R) (Room(R) ? H.hotelNo ? R.hotelNo?? R.price ? 50)} (c) {H.hotelName | Hotel(H) ? (?B) (?G) (Booking(B) ? Guest(G) ? H.hotelNo ? B.hotelNo?? B.guestNo = G.guestNo ?? G.guestName = ‘John Smith’)} (d) {H.hotelName, G.guestName, B1.dateFrom, B2.dateFrom | Hotel(H) ? Guest(G) ? Booking(B1) ? Booking(B2) ? H.hotelNo ? B1.hotelNo?? G.guestNo = B1.guestNo ?? B2.hotelNo = B1.hotelNo ? B2.guestNo = B1.guestNo ?? B2.dateFrom ? B1.dateFrom}