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Fiona races bmx around a circular dirt course. if the radius of the course is 70 meters, what is the total distance fiona covers in two laps of the race? a. about 30,772 meters b. about 15,386 meters c. about 879.2 meters d. about 439.6 meters e. about 219.8 meters23 points hurry

Agroup of farmers planned to clean 80 acres of wheat per day to finish the work on schedule. right before the work started, they received a new piece of machinery that them clean 10 more acres per day than originally planned. as a result of increased productivity in the last day before the deadline they only had to clean 30 acres. how many acres of wheat did the group of farmers have to clean?

Carbon- 14 is a radioactive form of carbon found in all living plants. after a plant dies, the carbon- 14 disintegrates. samples of similar living plants are used to determine the age of the remains. the amount of carbone-14 present after t years is given by the exponential equation n(t) = noe where no is the initial amount of carbon-14. the half-life of carbone-14 is 5600 years. charcoal from an ancient fire pit contains one third of earbon-14 found in similar living wood of the same size. find the age of the charcoal half-life is the time required for a quantity to reduce to half its initial amount