A chemist prepares a solution of magnesium fluoride by measuring out of magnesium fluoride into a volumetric flask and filling the flask to the mark with water. Calculate the concentration in of the chemist's magnesium fluoride solution. Be sure your answer has the correct number of significant digits.

Describe the difference between a. a hypothesis and a theory and b. an observation and an experiment.

Look at the spectrums of a star moving towards earth and a motionless star. which of these is a correct inference that can be draw from the observation of the two spectrums? (2 points) the spectrum of a motionless star is difficult to be viewed separately using oridinary telescopes. the spectrum of a motionless star is identical to the spectrum of a star which moves towards earth. the spectrum of a star shifts towards the red region when the star moves towards earth. the spectrum of a star shifts towards the blue region when the star moves towards earth.

Precision can be defined as the o exact center of a data set. o reproducibility of a measured value. o correlation between two variables that are measured in a data set agreement between a measured value and an accepted value.