A student finds a rock on the way to school. In the laboratory he determines that the volume of the rock is 25 cm, and the mass in 100 g. What is the density of the rock? 125 g/cm3
0.25 g/cm3
75 g/cm3
4 g/cm3

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.

In a copper wire, a temperature increase is the result of which of the following

Will mark brainliest how many electrons can be held in the energy level n = 4?