The data in the graph are the result of a paramecium being placed in a hypertonic salt solution.

A graph entitled Paramecium Contractile Vacuole Contractions has salt concentration on the horizontal axis and contractions per minute on the vertical axis. A very low salt concentration has 30 contractions per minute, low: 22, medium: 15, high: 8, very-high: 2.

What change would most improve the usefulness of the graph?
Replace the concentration descriptions with actual values.
Plot contractions per second instead of contractions per minute.
Remove the plotted points and just keep the line.
Remove the name of the organism from the title.

Calculate the number of kilojoules to warm 125 g of iron from 23.5°c to 78.0°c.

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.

Which of the following units is not an official si unit