A toy tractor sold for $256 in 1979 and was sold again in 1985 for $415. Assume that the growth in the value V of the collector's item was exponential CED a) Find the value k of the exponential growth rate. Assume V. = 256 k= (Round to the nearest thousandth.) e this Get more help - Clear arch Untitled* - Paint... Pre-Calculus - . Do Homework -.. CalculatorThe radioactive element carbon-14 has a half-life of 5750 years. A scientist determined that the bones from a mastodon had lost 68.1% of their carbon-14. How old were the bones at the time they were discovered? The bones were about | years old (Round to the nearest integer as needed.)\fPoints: 0 of 1 Save Country A has an exponential growth rate of 2.9% per year. The population is currently 4,367,000, and the land area of Country A is 40,000,000,000 square yards. Assuming this growth rate continues and is exponential, after how long will there be one person for every square yard of land? This will happen in year(s) (Round to the nearest integer.)