A graph titled heating curve of Substance A shows heat added in joules on the x-axis, and temperature in degrees celsius on the y-axis on a scale of 0 to 600. The graph has a diagonal line from the origin, point A, up to point B at 200 degrees Celsius. A horizontal line from B to C. A diagonal line from C up to D at 350 degrees Celsius. A horizontal line from D to E. A diagonal line from E to F at 625 degrees Celsius. What is the melting point of substance A? °C