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A discrete random variable Y takes values 0,1,3,6,10 with probabilities: y 0 1 3 6 10 P(Y=y) 0.15 0.25 0.20 p 0.18 What is the value of p for this to be a probability mass function? Then calculate the expected value of Y, E(Y). TI-84 online calculator

In a city, 35% of adults are smokers. Of the smokers, 25% exercise regularly; of the non-smokers, 50% exercise regularly. If a randomly selected adult is known to exercise regularly, what is the probability that the person is a smoker, given that they regularly exercise P(smoker∣exercises)? TI-84 online calculator

A company has 20 employees. Six (6) are managers, ten (10) are engineers, and four (4) are Technical specialists. In how many ways can the company select a CEO, a CFO, and a COO, given that only a manager can be the CEO, and the other two positions can be filled by any employee, with no one holding more than one position. TI-84 online calculator

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14. Using only the periodic table, arrange each set of particles by size, largest to smallest:O, P, Sa.    The size order is P > S > Ob.     The size order is P< S > Oc.    The size order is P> S< Od.    The size order is P > S > O

12. TNT has the chemical formula C7H5N3O6. How many grams of nitrogen are present in 25 g TNT? 1 mole of TNT=227.15 g/mola.    0.11 gb.    0.33 gc.    1.5 gd.    4.6 g -Find the number of moles TNT? -Total moles of Nitrogen in TNT? -Mass of nitrogen atoms in Sample?

5.What is the molecular formula for this compound? a.C2H4O2 b.C2H2O4                                                          c.C4H2O2 d.CH4O2

7.On July 10, 1913, the world-record highest air temperature was recorded to be 134°F at Furnace Creek Ranch in Death Valley, California. What is this temperature in degrees Celsius?(°F – 32) * 5/9 = °Ca.    42°Cb.    74°Cc.    106°Cd.    57°C

A 84.6419 g antique coin is thought to be gold. When the coin is placed in a graduated cylinder containing 15.53 mL of water, the water level rises to 24.64 mL. Calculate the density of the coin with right significant figures.  Volume of object in water = Final volume – Initial volume of water Density = Mass / Volume a.    9.29 g/mLb.    5.45 g/mLc.    0.738 g/mLd.    5.453 g/mL                                           

Workers health surveillance programmes are concerned about hazards that are present at the workplace which may cause ill-health to the worker.