Achemist is researching different sustainable fuel sources. she is currently working with benzene, which must be in liquid form for her to successfully conduct her research. the boiling point of benzene is 176° f, and the freezing point is 42° f.
part a: write an inequality to represent the temperatures the benzene must stay between to ensure it remains liquid.
part b: describe the graph of the inequality completely from part a. use terms such as open/closed circles and shading directions. explain what the solutions to the inequality represent.
part c: in february, the building's furnace broke and the temperature of the building fell to 20° f. would the chemist have been able to conduct her research with benzene on this day? why or why not?

Acell phone company offers two plans to its subscribers. at the time new subscribers sign up, they are asked to provide some demographic information. the mean yearly income for a sample of 40 subscribers to plan a is $45,000 with a standard deviation of $9,200. for a sample of 25 subscribers to plan b, the mean income is $64,300 with a standard deviation of $7,100. at the 0.025 significance level, is it reasonable to conclude the mean income of those selecting plan b is larger? assume unequal population standard deviations. hint: for the calculations, assume the plan a as the first sample. what is the decision rule? (negative amount should be indicated by a minus sign. round your answer to 3 decimal places.) compute the value of the test statistic. (negative amount should be indicated by a minus sign. round your answer to 2 decimal places.) what is your decision regarding h0 ? reject h0 fail to reject h0 compute the p-value. less than 0.01 between 0.01 and 0.025 between 0.025 and 0.05 between 0.05 and 0.10 greater than 0.10