It says that my first answer is right but that my last two are wrong. Can you help me?

Entered Answer Preview Result OO -[8/(x^5)] correct 0 0 incorrect 12 12 incorrect At least one of the answers above is NOT correct. Application of Derivatives Jocelyn Ybarra dT If T(a) = 2 + then The slope of the tangent line to Tat x = 6 is If T(x) is the temperature of a runner (in Fahrenheit F) at a distance x from the start line (in miles mi) find the rate at which the runners temperature is changing with respect distance at x = 3 is 12 degrees F per mile