Radioactive iodine isotope of half-life 8.0 days is used for the treatment of thyroid gland cancer. A certain sample is required to have an activity of 80 x 10^5 Bq at the time it is
given to the patient. Calculate the mass of the iodine-131 present in the sample to produce the required activity. Given the mass of iodine is 131g.​

When a neutrally charged atom loses an electron to another atom, the result is the creation of a. two charged atoms. b. two negatively charged atoms. c. two positively charged atoms. d. two neutrally charged atoms.

The place you get your hair cut has two nearly parallel mirrors 6.00 m apart. as you sit in the chair, your head is 2.00 m from the nearer mirror. looking toward this mirror, you first see your face and then, farther away, the back of your head. (the mirrors need to be slightly nonparallel for you to be able to see the back of your head, but you can treat them as parallel in this problem.) how far away does the back of your head appear to be?

The least penetrating form of radiation is