Scientists infer that early north american humans hunted the mastodon. carbon-14 dating of the rib bone indicates that 2.4 half-lives have passed since the mastodon was killed. approximately how many years ago did the mastodon die?

What is lincoln's purpose in writing this speech? question 1 options: to stress the difficulties of war to honor those who died in the war to call for an end to the war to call the country to join a new war

Over the last 90 years, scientists have added to the body of evidence supporting the big bang theory. what is the latest piece of evidence discovered in 2014?

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.