Cell 0721 710 SECOND SEMESTER EXAMINATION FOR THE DEGREE OF
BACHELOR OF SCIENCE
SCO 206: DATABASE SYSTEMS
TIME: 8.00 a. m. - 10.00 a. m.
DATE: Thursday,
23rd
August 2018
INSTRUCTIONS: Answer question ONE and any other TWO questions.
QUESTION ONE (COMPULSORY) (30 MARKS)
a) A car insurance company has a set of customers, each of whom owns one or more cars. Each car has
associated with it zero to any number of recorded accidents.
i) Construct an E-R diagram to represent the above scenario. (6 MARKS)
ii) Construct appropriate tables. (9 MARKS)
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Apressure vessel with an r/t 20 cannot be treated as thin walled vessel. a)-trune b)- false

Asimple speed reducer is composed of 2 spur gears. the pinion gear has a pitch diameter of 0.75" and 36 teeth while the driven gear has a pitch diameter of 4.0" and 192 teeth. a)-what is the diametral pitch of each gear? b)-if an electric motor rotating ccw at 3000 rpm is coupled to the pinion, what is the rotational speed of the driven gear? c)-if the torque delivered to the pinion is 1 n-m, what is the torque on the driven gear? d)-what is the power transmitted by the gear train?

In a unit cell of fcc structure, indicate the position of one of the tetrahedral interstitial sites by plotting the corresponding tetrahedron. do the same for one of the octahedral interstitial sites (in a separate fcc unit cell). mark the positions of all the tetrahedral and octahedral interstitial sites in the unit cells. how many equivalent tetrahedral sites and how many equivalent octahedral sites are contained in a fcc unit cell, respectively. what is the coordination number for a tetrahedral site and what is the coordination number for an octahedral site?