पर्यावरण में प्रवेश करने वाला वह पदार्थ जो अपनी प्राकृतिक प्रचुरता से अधिक सांद्रता में उपस्थित हो और हानिकारक प्रभाव उत्पन्न करता हो, कहलाता 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?