In NiCD battery, a fully charged cell is composed of nickelic hydroxide. Nickel is an element that multiple oxidation states. Assume the proportions of the states. Nickel Charge Proportions Found
0 0.17
+2 0.35
+3 0.33
+4 0.15
a. Determine the cumulative distribution function of nickel charge.
b. Determine the mean and variance of the nickel charge.

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Solve the following inequalities and show the solution on a number line. 3/4 (2x-7) ≤ 5

An automobile assembly line operation has a scheduled mean completion time, μ, of 12 minutes. the standard deviation of completion times is 1.6 minutes. it is claimed that, under new management, the mean completion time has decreased. to test this claim, a random sample of 33 completion times under new management was taken. the sample had a mean of 11.2 minutes. assume that the population is normally distributed. can we support, at the 0.05 level of significance, the claim that the mean completion time has decreased under new management? assume that the standard deviation of completion times has not changed.