Ms. Cleary investigates the relationship between air pressure and weather. On Monday, she observes that the air pressure is low, and it is stormy outside. Which of the following explains why Ms. Cleary should continue collecting the same type of data for one month? A. It will increase the reliability of the results.

B. It will decrease the accuracy of the results.

C. It will control the variables in her investigation.

D. It will change the hypothesis of her investigation.

The content of manganese (mn) in steel was determined spectrophotometrically and with the use of the standard addition method. an unknown sample of mn from a digested steel sample gave an absorbance of 0.185 when analyzed spectrophotometrically. when 5.00 ml of solution containing 95.5 ppm mn was added to 50.0 ml of the unknown steel solution (digested sample), the absorbance was 0.248. calculate the concentration, in parts-per-million (ppm), of mn in the digested steel sample solution.