एक पाण्याची टाकी 2/3 भरलेली आहे. ती टाकी एका नळाने 30 तासात भरते तर दुसऱ्या नळाने 10 तासात रिकामी होते. जर दोन्ही नळ एकाच वेळी चालू केले तर ती टाकी पूर्णपणे रिकामी होण्यास किती तास लागतील ?

Choose the correct question tag to fill in the blank.
I am the happiest man in my town, ________?

A hardware or software device that is able to modify data according to instructions is called a ________.
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After the word, four meanings are given. Choose the correct alternative from the following:
Directory

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'to dictate letters' mean

The underlined idiom in the following sentence means
People these days want to be rich overnight; naturally they try to earn money by hook or crook.