Which equation is balanced? A) Mg3N2 + H2O 3MgO + 2NH3
B) C3H8 + 5O2 H2O + 3CO2
C) Zn + 2HCl ZnCl2 + H2
D) 3H2SO4 + 2Fe Fe2(SO4)3 + H2

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?

Lab reagent, hypothesis test. a reference solution used as a lab reagent is purported to have a concentration of 5 mg/dl. six samples are taken from this solution and the following concentrations are recorded: (5.32, 4.88, 5.10, 4.73, 5.15, 4.75) mg/dl. these six measurements are assumed to be an srs of all possible measurements from solution. they are also assumed to have a standard deviation of 0.2, a normal distributin, and a mean concentration equal to the true concentration of the solution. carry out a significance test to determine whether these six measurements provide reliable evidence that the true concentration of the solution is actually not 5 mg/dl.

Identify arrows pointing to bonding electrons. done h-0-0-h ) intro