Balance and state of the reactions are precipitation, acid/base, or oxidation/reduction reactions. a) fe + o2 -> fe2o3 b) br2 + fe(no3)2 + kno3 -> kbr + fe(no3)3 c) ba(oh)2 + hno3 -> h2o + ba(no3)2 d) naf + mg(no3)2 -> mgf + nano3

Which of the following is an example of how telecommunication devices people do their jobs? a.) a security guard checks the time using a digital watch. b.) a banker does some quick math using a solar calculator. c.) a nurse uses a digital thermometer to take a patient’s temperature. d.) a construction worker reports in to his office using a cell phone.