I don’t understand please help

1) these are barrel shaped microtubules in most animal cells, that organize the spindles during cell division

Which of the following nuclei would be the least stable a 2 protons, 2 neutrons b 1 proton 1 neutron c 1 proton 3 neutrons d 1 proton 2 neutrons

Which is true concerning the products and reactants of photosynthesis and cellular respiration? a. the products of photosynthesis are sugars and the reactants of cellular respiration are starches. b. the products of photosynthesis are reactants in cellular respiration. c. oxygen is needed for photosynthesis and is given off in cellular respiration.