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A large intro class of two thousand students did a bead box activity to estimate the proportion of blue beads in a very large box of beads.  Each student took a random sample of size 100 and recorded their sample proportion for the color blue.  A dotplot of these 2000 proportions is found below. Your sample proportion was 0.72.   Based on the sampling distribution found above, which of the below options is closest to the true population proportion of blue beads in the box?

Researchers were interested in the correlation between the minutes spent at the lunch table and amount of calories consumed for children who are in first grade. They sampled n = 18 first grade children where they found the sample correlation to be r = -0.65, with a margin of error = 0.12. What is the correct calculation for the interval estimate for the population correlation? [answer1]

Overall, 85% of Americans go online on a daily basis, according to a Pew Research Center survey conducted in January 2021. Responses came from a random sample of n = 2,002 U.S. national adults. The population of interest is [answer2]. The corresponding parameter symbol is [answer1].  The best estimate for the parameter is [answer3]=[answer4] Since this survey used [answer5], we [answer6] generalize our findings to the population of interest. 

Two researchers completed the same study when considering the same hypothesis test. Researcher A obtained a p-value of 0.10. Researcher B obtained a p-value of 0.13. Based on this information, the p-value from researcher [answer1] provides stronger evidence against the null and in favor of the alternative.  Use a significance level of 0.05. Researcher A should [answer2] the null hypothesis. Researcher B should [answer3] the null hypothesis.

We have access to the complete dataset of all ages (in years) at death for First Ladies of the U.S. who have passed. From this data set we know that the average age at death is 71.7 years. You are interested in how the sample statistics vary for different samples of size n=15 from this population. A sampling distribution is constructed where one of the samples is used to create a bootstrap distribution. This sample has mean: x-bar = 78 years. Below are boxplots of the sample of size n = 15, the sampling distribution, and the bootstrap distribution (although not necessarily in that order!). Use all of the provided information to select the correct reason for each Boxplot identification. Boxplot A is the bootstrap distribution because it is centered at the [answer3] and has an estimated standard error that is roughly equal to the standard error found with the [answer4]. Boxplot B is the sample of n = 15 because it is centered at the [answer5] where the sample standard deviation (s) is [answer6] the value of the standard error found with the sampling distribution.  Boxplot C is the sampling distribution because it is centered at the [answer1] and has a standard error that is roughly equal to the estimated standard error found with the [answer2].

What is the mass in grams of MgCI₂ that can be produced from [x]0 moles of Cl₂ gas reacting with excess magnesium? Mg(s) + Cl₂(g) → MgCI₂(s)

A medical laboratory test is run using a [x] µL blood sample. What is this volume in milliliters? Show your work using dimensional analysis.

What would be the charge on an atom of lead which only has 78 electrons?  [sign][magnitude]

There are three isotopes of an element with the following percent abundances; 20X = 19.992 amu (90.51%), 21X = 20.993 amu (0.27%), 22X = 21.991 amu. What is the average atomic mass in amu of X? Show your work and give your answer to 2 decimal places.

The fictional element Chaffium (symbol Ch) makes two oxyanions: ChO3¯ and ChO4¯ What would be the name of ChO4¯? Explain your reasoning. Note: The fictional element name is a Latin word that ends with -ium like many real elements. Just use the same rules as you would with a real element name.