Uranium-235 undergoes fission to produce two neutrons per fission event. if a neutron-absorbing material is mixed in with this sample so that the rate of neutron production drops down to 0.5 neutrons per fission event, which of the following will be effective at achieving a critical mass? check all that apply. surround the sample with a deflective material to prevent neutrons from escaping to the surroundings. add more absorbent material. compress the uranium-235 sample.

Question 1 which of the following allows cells to take in fluids? a. phagocytosis b. pinocytosis c. exocytosis d. receptor-mediated endocytosis question 2 molecules move along their concentration gradient (from areas of high concentration to low concentration) using active transport mechanisms. a. true b. false question 3 which of the following powers active transport (ie. provides the energy for)? a. glucose b. transport proteins c. atp d. phospholipids question 4 what type of lipid is a major component of the plasma membrane? a. cholesterol b. phosopholipids c. proteins d. triglycerides