Answer: C) Assam Explanation: Gas and Oil fields are located in Naharkatiya, Assam. Oil from the fields is sent to Nunmati for refining and gas is made into electricity at Namrup.

Answer: B) Myogenic heart Explanation: Hearts are of several types. In some invertebrates the heart is simulated by the nervous system to do its work. Such hearts are called Neurogenic hearts. The Human heart is myogenic. i.e, it recieves the stimuli for contraction from the muscular node called sinu-auricular node or pace maker.

Answer: D) Tuber Explanation: Tuber is considered as a modified stem. These type of stems carry out special functions that are important for the plant to survive. Tubers serves as a food reserve and bearing buds wherein new plants can grow.

Answer: B) 23 Explanation: If he wants to give these books equally to 2 of his friends, then 1 book will remain, it means possible number of books = 15,17,19,21,23,25,27,29If he wants to give these books equally to 3 of his friends, then 2 books will remain, it means possible number of books = 17,20,23,26,29If he wants to give these books equally to 4 of his friends, then 3 book will remain, it means possible number of books = 15,19,23,27common number is only 23 so it will be answer