A solid cone of height 36 cm and radius of base 9 cm is melted to form a solid cylinder of radius 9 cm and height 9 cm. What percent of material is wasted this process?
Among four books, Book1 is twice as heavy as Book 2. Book 3's weight is half of Book 2's weight. Book 4 is 60 grams more as compared to Book 2 but 60 grams less as compared Book 1. Which book is heaviest?