The length of arc ab (the minor arc) is 40 cm. what is the circumference of c

Yes, that is the correct formula. to solve this problem given the number of years, plug in the number of years for t and plug the whole thing into the

First step is to get rid of the square root. remember that a square root is the same as raising to the (1/2) power. see below: multiply exponents per exponent rules to get: remember you subtract exponents from the denominator and add exponents in the numerator so: simplify further: so a is the correct choice. if you don't understand this google exponent rules and it will you understand. look at the image results.