Viewed Questions
Scanner $A$ can scan a document in 3 hours. Scanner $B$ takes 5 hours to do the same job. If both scanners are used, how long will it take for the document to be scanned?
Rational Expressions
Rational Equations and Problem Solving
Why is the signaling pathway that activates NF-kB considered to be relatively irreversible compared with cytokine or $\mathrm{RTK}$ signaling pathways? Nonetheless, NF-kB signaling must be down-regulated eventually. How is the NF-\kappaB signaling pathway turned off?
Mesityl oxide is an industrial chemical prepared by an aldol condensation. From what organic starting material is mesityl oxide prepared? It often contains about $10 \%$ of an isomer with the same carbon skeleton. What is the most likely structure for this contaminant?
Enols and Enolates
Conjugation Effects in $\alpha, \beta$…
Outline a synthesis of the compound shown from methyl vinyl ketone and diethyl malonate.
Questions asked
What is the sample standard deviation given the following information? Gross counts = 2,598,600 in 10 minutes Background counts = 50,075 in 6 minutes The correct choice is not d. a. 103 cpm b. 165 cpm c. 392 cpm d. 518 cpm
What is the average of the following numbers? 19801, 19593, 19534, 19795, 19532, 19745, 19508, 19748, 19480, 19397 The answer is not choice a. a. 19541 cpm b. 19613 cpm c. 19741 cpm d. 19768 cpm
Convert 2.5 mCi to MBq. Remember that 1 Ci = 3.7 x 10^10 Bq Choice a is incorrect. a. 0.092 MBq b. 0.67 MBq c. 67.6 MBq d. 92.6 MBq
131I has a physical half-life of 8.1 days and a biological half-life of 180 days (because of its tendency to concentrate in the thyroid). If 25 mCi of the radionuclide is administered to a patient whose thyroid is functioning normally, what activity can be expected to be found in this patient after 84 hrs? a. 0.17 µCi b. 13.6 µCi c. 18.3 mCi d. 29.2 mCi e. None of the above
131I has a physical half-life of 8.1 days and a biological half-life of 180 days (because of its tendency to concentrate in the thyroid). If 25 mCi of the radionuclide is administered to a patient whose thyroid is functioning normally, what activity can be expected to be found in this patient after 84 hrs? a. 0.17 µCi b. 13.6 µCi c. 18.3 µCi d. 29.2 µCi e. None of the above
What is the sample standard deviation given the following information? Gross counts = 2,598,600 in 10 minutes Background counts = 50,075 in 6 minutes a. 103 cpm b. 165 cpm c. 392 cpm d. 518 cpm
Given the following numbers, determine if they should be used or discarded. N1 = 100,075 cpm and N2 = 110,111 cpm. a. it is okay to use these samples b. it is not okay to use these samples c. it is questionable whether to use these samples d. none
Using the following numbers, do these numbers pass the chi square test? 19801, 19593, 19534, 19795, 19532, 19745, 19508, 19748, 19480, 19397 a. yes b. no c. questionable, redo the test d. none
Using the following numbers, what is the % error (100% divided by squared root of mean)? 19801, 19593, 19534, 19795, 19532, 19745, 19508, 19748, 19480, 19397 a. 0.71% b. 7.14% c. 71.4% d. 714.04%
Using the following numbers, what is the third expected standard deviation confidence interval (mean +/- 3 times the square root of mean)? 19801, 19593, 19534, 19795, 19532, 19745, 19508, 19748, 19480, 19397 a. 19320 - 19906 cpm b. 19180 - 19893 cpm c. 19193 - 20033 cpm d. 19175 - 20051 cpm