Use the Relational Algebra to express the following queries:
(a) Find the makes of all cars manufactured by ?Mercedes/Chrysler?
(b) Find the names and addresses of all dealers who sell Plymouths (i.e., cars with make
'Plymouth'.)
(c) Find the addresses of dealers that sell at least one make of car manufactured by a company
incorporated in Japan.
(d) Find all dealers who don't sell any car manufactured by ?Mercedes/Chrysler?.
Consider the following schema:
Manufacturer(MName,HQAddress,Country)
Car(Make,ModelNum,MName,Kind)
Dealership(DName,DAddress)
Sell(DName,Make,ModelNum)
Solution:
(a) 
(b) 
(c) 
(d) 
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What class of IPv4 address includes the first octet numbers from 192 to 223?
A) Class B B) Class A C) Class D D) Class C E) Class E
The IAL requires the agent to advance the arrow for the alphabetically earliest URL. Show that the IAL is effective by explaining how an agent would know which list has the “alphabetically earliest” URL, and so must have its arrow advanced.
What will be an ideal response?