What is being described in the following definition: an opening in the floor, platform, or pavement that measures 12 inches or more, and through which persons may fall. a. floor hole b. floor opening c. wall opening d. railing

Select all the correct answers. which changes will increase the rate of reaction during combustion? decreasing the area of contact between the reactants adding more oxygen to the reaction removing heat from the reaction changing the reactants from solid form to powdered form lowering the exposure of the reactants to air