some people have the ability to roll their tongues (rollers) while other people cannot roll their tongues (non-rollers) . What was the dependent variable, independent variable & one fixed variables ?​

answer; i believe that the best answer is (secondary cardiac arrest due to

the answer to your question is b

enzyme active site and substrate specificity

enzymes bind with chemical reactants called substrates. there may be one or more substrates for each type of enzyme, depending on the particular chemical reaction. in some reactions, a single-reactant substrate is broken down into multiple products