The number of years N(r) since two independently evolving languages split off from a common ancestral language is approximated by N(r) = - 5000 In r where r is the proportion of the words from the ancestral language that are common to both languages now. ..... a. N(0.9) = (Round to the nearest tens place.) b. N(0.4) = (Round to the nearest hundreds place.) c. N(0.2) = (Round to the nearest thousands place.) d. How many years have elapsed since the split if 60% of the words of the ancestral language are common to both languages today? years have elapsed since the split. (Round to the nearest hundreds place.) e. If two languages split off from a common ancestral language about 1000 years ago, find r. r= (Round to the nearest tenth as needed.)