Radiocontrast dyes are considered safe because the isotopes have short half-lives and the isotopes coat the gastrointestinal tract and are not absorbed by normal tissue. if a patient ingests 10.0 mg of iodine, how long until the iodine-134 is 99% out of the patient's system if the half-life of iodine-134 is 52.6 minutes?

Total solidification times of three casting geometries are to be compared: a sphere, a cylinder, in which the length-to-diameter ration - 1.0, and a cube. volume = 1000 cm^3 for all three shhapes, and the same casting alloy is used. a) determine the solidification times of each geometry b) based on the results of part (a), which geometric element would make the best riser? c) if the mold constant = 3.5 min/cm^2 in chvorinov's rule, compute the total solidification time for each casting.