Hi! , here's my code

The value in number should be -17.099... But i get -39.379... What's the problem here?Code:

#include <math.h>

#define M_PI 3.14159265358979323846

// Calculate Constant

double constant()

{

const double figure = 7.9454E-18;

double number = log (figure);

return -10 * number ;

}