किशोरावस्था में लड़कियों में यौवनारंभ के दौरान पहली बार मासिक धर्म (menstruation) की शुरुआत को जैविक रूप से क्या कहा जाता है?

The Dandi March, also known as the Salt Satyagraha, was led by which influential leader?

Which act formally granted independence to India, marking the end of British rule?

Who was the key figure in establishing the Indian National Congress?