Solve the problem.A data set consists of 542 lightbulbs. Over a long period of time, the lifetimes of those lightbulbs have been tested. It has been found that the mean and standard deviation are known and the lifetimes of the bulbs are normally distributed. What number of bulbs within this data set will have lifetimes that lie between the mean and two standard deviations below the mean? Round your answer to the nearest whole number.
A. 185
B. 268
C. 74
D. 259
Answer: D
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Find the area of the specified region.Inside the cardioid r = ?(1 + sin ?), ? > 0
A. 
- 2?2
B. 
C. 2??
D. 
+ 2?2
Begin by graphing the standard absolute value function f(x) = 
. Then use transformations of this graph to graph the given function.g(x) = 2
A. 
B. 
C. 
D. 
Solve the equation. 
= -3.35
A. -3.35 B. No solution C. -3.35, 3.35 D. 3.35
Solve the problem.The concentration C (arbitrary units) of a certain drug in a patient's bloodstream can be modeled using 
where t is the number of hours since a 500 milligram oral dose was administered. Using the TABLE feature of a graphing utility, find the time at which the concentration of the drug is greatest. Round to the nearest tenth of an hour.
A. 5.3 hours B. 3.8 hours C. 4.6 hours D. 6.1 hours