The element in period 4 and group 8

Mike and mitchell decide to have a foot race. they mark off a stretch of 100 yards, and recruit cindy to work the stopwatch. after running the race and looking at the results, cindy declared that mitchell was the fastest. so how did the boys times compare?

Pl what kind of reaction is this? nahco3 + h2o → co2 + naoh + h2o -composition -decomposition -single replacement -double replacement im leaning more toward single replacement. if im wrong can you explain whyy?

Metric temperature is measured in celsius and fahrenheit. true or false