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True or False:If the and , the appropriate decision is to REJECT the null hypothesis.

A chemist is studying the properties of both CaSO4 and PbSO4. They are both white powders.  Neither conducts electricity until placed in water (remember that electrolytic solutions are created due to the presence of ions in solution). 1. The chemist places excess CaSO4(s) in a beaker with 100 mL of water.  She also adds excess PbSO4 in another beaker containing 100 mL of water.  After stirring, she checks the electrical conductivity and determines that it is higher in the CaSO4 beaker.  Which compound is more soluble in water – CaSO4 or PbSO4?  Justify your answer; 2. View the diagram below.  Describe in detail what the PbSO4 beaker would look like in comparison to the CaSO4 beaker;   3. The chemist then tries to increase the solubility of CaSO4 by adding 20.0 mL of 1.0 M H2SO4 to the beaker and observes additional precipitate.  Explain.

Suppose you roll this weighted die twice. What is the probability that you roll either a 4 on the first roll or a 6 on the second roll?

Use this set-up for Problems 53-56: A Quinnipiac poll performed on January 28-February 1, 2021 asked Americans, “Are you willing to get a COVID-19 vaccine, or not?” 30% of respondents said they were not. You wonder whether this proportion has changed in the past few years, so you conduct a poll of 100 Americans and ask the same question. 25 people in your sample were unwilling to get the COVID-19 vaccine. Suppose you set . What hypotheses should you set-up to determine if the percentage has changed since the initial poll?

Use this set-up for Problems 9-10: A 5-number summary for a set of data is 10, 23, 32, 39, 46. Which of the following statements is TRUE?

Data set: systolic blood pressures of 20 randomly selected patients at a blood bank 135     120     115     132     136     124     119     145       98     110 125     120     115     130     140    105     116     121     125     108 Find the sample standard deviation for the data set.  Round to 2 decimal places.

To make a 1:5 dilution of a stock solution: you must add what volume of stock solution to 1 mL of deionized water?  

Tables and formula sheets are attached at the bottom of the test.

Which property of proteins best determines the electrophoretic pattern in SDS-PAGE under reducing conditions?

A monoclonal antibody shows strong binding to its target protein in a Western blot but fails to work in immunoprecipitation. The MOST likely explanation is: