I’d say b is the better option because d is starving yourself which creates unhealthy habits, c would cause yo yo dieting or binging because you treat food as a reward which is a toxic mindset, and a same explanation. I wish there was an answer to just track what you eat, have daily exercise and enjoy in moderation, though.
Water expands when it freezes (that's why you should never put closed, fully filled water bottles in the freezer !)
-- 'Ca' (Calcium) is an element.
-- The proton has a positive charge.
-- Nuclear fusion results in the synthesis of atoms of new elements.
-- H₂O (water) is a chemical compound.
-- Nuclear fission is a decay of the nucleus.
-- The atomic number of an element is the number of protons
in each atom of it.
-- I suppose you're using the Greek letter <span>η ('eta', not 'nu')
to represent the neutron.
-- I suppose you're using ' e ' to represent the electron.
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