Prompt the user to enter a starting guess to use as the first value for the newton-raphson method. if this guess causes the derivative of the temperature function to be zero (i. e. if t ′ ) = 0 ), the method will immediately fail due to a division by zero. check if the initial guess will cause the method to fail. if so, prompt the user to enter a new initial guess until the user enters a valid value. if the user does not enter an acceptable guess after 3 attempts, produce an error and terminate the program.