Which statement is correct? Flat files use foreign keys to uniquely identify tables,
O Flat files use foreign keys to secure data.
Aforeign key is a primary key in another table.
A foreign key uniquely identifies a record in a table.
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Apiston-cylinder with a volume of 0.25 m3 holds 1 kg of air (r 0.287 k/kgk) at a temperature of 100 c. heat transfer to the cylinder causes an isothermal expansion of the piston until the volume triples. how much heat is added to the piston-cylinder?

Water in a partially filled large tank is to be supplied to the roof top, which is 8 m above the water level in the tank, through a 2.2-cm-internal-diameter pipe by maintaining a constant air pressure of 300 kpa (gage) in the tank. if the head loss in the piping is 2 m of water, determine the discharge rate of the supply of water to the roof top in liters per second.

Draw the engineering stress-strain curve for (a) bcc; (b) fcc metals and mark important points.