The Foley Products Company has designed a new blend of concrete they believe will be twice as strong as their current high quality concrete. This new blend of concrete is believed to produce batches with a population mean strength of 15,000 psi and a population standard deviation of 2,000 psi. To validate this belief, they collect a random sample of 49 concrete batches out of all the batches produced at their plant in a particular week. The mean strength of the random sample of 49 concrete batches is measured to be 14,731 psi. Select the correct description of the population in this study.

this may not be at all, but i use the same website you're using for school, and if i'm stuck doing one of these i try to look for it on the section.

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sin y = 7/q

7 is the opposite side length, q is the hypotenuse

tan y = 7/r

7 is the opposite side length, r is the adjacent side length

using sohcahtoa ^^^^

cos y = adjacent/hypotenuse

cos y = r/q

large crystals result from very slow cooling.

evaporation of water: this would produce an evaporite which is a sedimentary rock. like a salt pan in a desert. not possible to have volcanic rocks originate this way.

crystalization in molten earth: slow cooling over time. (hundreds to millions of years)

crystalization at earth's surface: this results in fast cooling. (a few hours to a few months or years)

crystalization from cooling off hot water: that would be a hydrothermal deposit. while associated with volcanics they are not volcanic rocks themselves and usually occur fairly rapidly.

17,000 is the correct answer.