4. stairs are considered hazardous when a. the width of the treads does not strictly comply with codes. b. risers are less than 73/4 inches high. c. they're covered with carpeting. d. the height of the risers varies by more than 3/8 inch.

answer; ///(true)/// fusion occurs in the sun's core;

radiative zone

explanation    

radiative zone is the layer of the sun which energy is transferred away from the core by radiation. although, the core is the only part of the sun that produces an appreciable amount of heat through fusion. in fact, 99% of the energy produced by the sun takes place within 24% of the sun's radius.