What is the time for starting the Duha prayer, the time for its end, and the best hour for performing it?

Question:
May Allah reward you and do you good. In her second-to-last question, she asks: What is the time for the Duha prayer in terms of the clock? May Allah reward you. Is it valid if performed half an hour before the adhan for the midday prayer?

Answer:
Yes. The time for the Duha prayer begins when the sun has risen the length of a spear above the horizon and continues until just before the sun reaches its zenith. It continues until just before the sun stands still at the center of the sky. When the sun is level with the heads, the time of prohibition begins until the sun moves from the heads toward the west. All this time, from when the sun rises the length of a spear until it stands still at the center of the sky, level with the heads, is the time for the Duha prayer. And the later it is performed, the better it is. His saying (peace and blessings be upon him) means when the heat of the sun has passed over the earth. Yes.