Think back to your knowledge of the carbon cycle. Some human activities increase the levels of CO2 in the atmosphere. In which year does CO2 concentration seem to make a pivotal turn? What are some human activities that could have influenced CO2 levels in this period?

How have the greenhouse gasses increased from the year 2000 to 2018

Consider this initial-rate data at a certain temperature for the reaction described by

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.