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What must happen before a body cell can begin mitotic cell division

Sulfuric acid (a component of acid rain) reacts with limestone (calcium carbonate) to produce calcium sulfate and carbon dioxide. this damages buildings and statues made of limestone. which solution of sulfuric acid will damage these structures more quickly? a. 0.001% b. 0.005% c. 0.010% d. 0.015%

Which compound contains both ionic and covalent bonds? a) hbr b)cbr4 c)nabr d) naoh