Chromium-51 is used in imaging red blood cells and has an effective half-life of 27 days. If a dose with an activity of 24 μCi is given to a patient, how long will it take for the patient to have less than 3 μCi present?
Express your answer as an integer.

Pls! plant cells and animal cells were observed under a microscope. the characteristics of two cells are listed below. cell p: does not capture sunlight cell q: has cytoplasm but no chloroplast which statement about the two cells is correct? cell q also has a cell wall. cell q also has large vacuole. cell p also has a large vacuole. cell p also has a cell membrane.

What method(s) do plants use to obtain nitrogen? select all that apply. absorb it from the atmosphere use bacteria to convert nitrogen to usable form obtain usable nitrogen compounds from the soil absorb nitrogen from water taken in at the roots

Ammonium perchlorate nh4clo4 is the solid rocket fuel used by the u.s. space shuttle. it reacts with itself to produce nitrogen gas n2 , chlorine gas cl2 , oxygen gas o2 , water h2o , and a great deal of energy. what mass of nitrogen gas is produced by the reaction of 2.1g of ammonium perchlorate?