Which of these resources is used worldwide to make construction products pottery and porcelain

"d.) carbon dioxide and hydrogen sulfide"

there's the proffessional site that will you.

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

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