The half-life of a sample of asatine As-210 is about 8 hours. How many half-lives must pass for only 25 grams of a 200-gram sample to remain?
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How will the emission of an alpha particle affect the atomic number of an atom

For a patient with the following pes statement and interventions, which would be the most appropriate monitoring and evaluating data? pes statement: inadequate calcium intake related to food and nutrition related knowledge deficit as evidenced by statements that the only dietary source of calcium is milk and she believes that she is lactose intolerant. patient’s nutrition prescription is for a diet providing 1200 mg calcium per day. patient was provided with in-depth nutrition education on alternative dietary and supplement sources of calcium. a. calcium intake (at subsequent visit) b. knowledge assessment by asking patient to identify food sources from menus and shopping list (at the end of the current visit) c. serum calcium (at next visit) d. both a and b e. both a and c

Can someone me with questions 15 to 17 plz.