फ़ेलडस्पार (Feldspars) खनिजों का निर्माण मुख्य रूप से किस प्रक्रिया द्वारा होता 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?