for the chemical reaction h2 + co2 → h2o + co, the energy contained in the reactants is 394 kj, and the energy contained in the products is 352 kj, assuming 1 mol of each substance is present. which of the following statements is true? a. 42 kj is released, and the reaction is exothermic. b. 42 kj is absorbed, and the reaction is exothermic. c. 42 kj is absorbed, and the reaction is endothermic. d. 42 kj is released, and the reaction is endothermic

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.