किस गैर-संभाव्यता प्रतिचयन (non-probability sampling) विधि में विशिष्ट विशेषताओं के आधार पर उपसमूह बनाना और फिर प्रत्येक उपसमूह से प्रतिभागियों की एक निश्चित संख्या का चयन करना शामिल है?

The 'Drain of Wealth' theory was propounded by which Indian nationalist leader?

Which event is considered the turning point in Mahatma Gandhi's leadership in the Indian independence movement?

Which African leader is known for his non-violent opposition to colonial rule?