4541: There are 10 identical coins and each one of them has H engraved on its one face and T engraved on its other face. These 10 coins are lying on a table and each one of them has H face as the upper face.
In one attempt, exactly four (neither more nor less) coins can be turned upside down. What is the minimum total number of attempts in which the T faces of all the 10 coins can be brought to be the upper faces ?
4542: Which one of the following is not in the State List under the Constitution of India?
(a) Fisheries
(b) Agriculture
(c) Insurance
(d) Betting and Gambling
4543: Painted greyware is attributed to
(a) Vedic period
(b) Guptas
(c) Mauryas
(d) Indus valley civilisation
4544: The sun derives its energy from:
(a) Nuclear fission reactions.
(b) Nuclear fusion reactions.
(c) Oxidation of helium.
(d) Fission of noble metals.
4545: Which one of the following plants can fix nitrogen from air?
(a) Rice
(b) Wheat
(c) Pea
(d) Maize