Write the following as triggers. in each case, disallow or undo the modification if it does not satisfy the stated constraint. the problems are based on our running movie example:

movies(title, year, length, genre, studioname, producerc#)
starsin(movetitle, moveyear, starname)
moviestar(name, address, gender, birthdate)
movieexec(name, address, cert#, networth)
studio(name, address, presc#)

you may assume that the desired condition holds before any change to the database is attempted. also, prefer to modify the database, even if it means inserting tuples with null or default values, rather than rejecting the attempted modification.

a. assure that at all times, any star appearing in starsin also appears in moviestar.
b. assure that at all times every movie executive appears as either a studio president, a producer of a movie, or both.
c. assure that every movie has at least one male and one female star.

Suppose that xtel currently is selling at $40 per share. you buy 500 shares using $15,000 of your own money, borrowing the remainder of the purchase price from your broker. the rate on the margin loan is 8%. a. what is the percentage increase in the net worth of your brokerage account if the price of xtel immediately changes to (a) $44; (b) $40; (c) $36? (leave no cells blank - be certain to enter "0" wherever required. negative values should be indicated by a minus sign. round your answers to 2 decimal places.) b. if the maintenance margin is 25%, how low can xtel’s price fall before you get a margin call? (round your answer to 2 decimal places.) c. how would your answer to requirement 2 would change if you had financed the initial purchase with only $10,000 of your own money? (round your answer to 2 decimal places.) d. what is the rate of return on your margined position (assuming again that you invest $15,000 of your own money) if xtel is selling after one year at (a) $44; (b) $40; (c) $36? (negative values should be indicated by a minus sign. round your answers to 2 decimal places.) e. continue to assume that a year has passed. how low can xtel’s price fall before you get a margin call? (round your answer to 2 decimal places.)

You decide to invest in a portfolio consisting of 25 percent stock a, 25 percent stock b, and the remainder in stock c. based on the following information, what is the expected return of your portfolio? state of economy probability of state return if state occurs of economy stock a stock b stock c recession .16 - 16.4 % - 2.7 % - 21.6 % normal .55 12.6 % 7.3 % 15.9 % boom .29 26.2 % 14.6 % 30.5 %

On january 15, the end of the first biweekly pay period of the year, north company’s payroll register showed that its employees earned $32,000 of sales salaries. withholdings from the employees’ salaries include fica social security taxes at the rate of 6.2%, fica medicare taxes at the rate of 1.45%, $3,000 of federal income taxes, $772 of medical insurance deductions, and $260 of union dues. no employee earned > $7,000 in this first period. prepare the journal entry to record north company’s january 15 (employee) payroll expenses and liabilities.