Which of the following best describes why we see the moon at different phases? A. We are only seeing portions of the moon when its orbit is closest to the Earth.

B. We are only seeing portions of the moon that is reflecting sunlight.

C. We are only seeing portions of the moon that is reflecting Earth's atmosphere.

D. We are only seeing portions of the moon that is blocking sunlight.

Which best describes why nh4+ can form an ionic bond with cl-?

What forms when chemical reactions combine pollution with sunlight?

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.