Cell Membrane part 3!! Please help

Select all the correct answers. lactobacillus is a bacteria that live inside humans. these bacteria live on the nutrients from our bodies. they to keep our gut clean and healthy. s. typhi is a bacteria that enter our bodies through contaminated food. this bacteria causes infections in the body. based on this information, which two statements about the association between these bacteria and humans are true? a. lactobacillus shares a parasitic relationship with humans. b. s .typhi shares a parasitic relationship with humans. c. both lactobacillus and s. typhi share a parasitic relationship with humans. d. both lactobacillus and s. typhi share a mutualistic relationship with humans. e. lactobacillus shares a mutualistic relationship with humans, and s. typhi shares a parasitic relationship multiply chrse

Ihave no idea how to solve these. plus there's another question that is 2) a 10 kilogram meteorite is collected in space and brought back to earth. it is composed of 1.25 kg of uranium-238 and 8.75 kg of lead-206. how many u-238 half lives have passed? what is the approximate age of the meteorite?

Aragonite shells of clams, snails, or scleractinian corals may be preserved unaltered in cenozoic deposits, but they are generally dissolved or recrystallized in older deposits. true or false