Find the wrong term in the series: 1, 3, 7, 15, 27, 63, 127

In the sequence 4727235974752479478471, how many '7's are there which are immediately preceded by '4' but NOT immediately followed by '2'?

What is the suffix (pratyay) in the Hindi word 'Aitihasik' (historical)?

Choose the correct article for the blank: 'A computer is ____ electronic device which stores information in it.'

Which disease is caused due to a lack of Vitamin A?