Answer: D) Refraction of light & Total Internal Reflection of light Explanation: A Mirage is a naturally occurring optical phenomenon in which light rays bend to produce a displaced image of distant objects or the sky. It is caused due to Total internal Reflection. It is an optical illusion observed in deserts or hot summer days due to which a person sees a pond of water some distance ahead of him in which the surrounding objects appear inverted. How Mirage Forms:: 1. The temperature of other layers of atmosphere goes on decreasing as we go up.2. Therefore density and refractive index of air changes as one goes up.3. Thus a ray of light,gets refracted more and more away from the normal.4. At a particular angle when a ray of light exceeds critical angle, total internal reflection takes place and ray of light gets reflected in the same medium.5. when the reflected ray reaches our eye, it appears as coming from tree or sky .6. Hence the inverted image of tree creates an impression from a pond of water.

Answer: B) DHLRX Explanation: The logic behind the sequence given in the question is +4, +4, +6, +6Therefore, the sequence which follows the same logic in the given options is DHLRX.

Answer 1) dRashmi is the daughter of Amit who is son of Veena.Therefore, Veena is Grand mother of Rashmi. Answer 2) bVandana's sister is Vishal's brother's wife.Therfore, Vishal is Vandana's Brother-in-law. Answer 3) cYashwanth is son of Avinash who is the son of Rohit Agarwal.Therefore, surname of Yashwanth is Agarwal.

Answer: A) Corona Explanation: The outermost layer of the sun is called The Corona.   The inner layers are the Core, Radiative Zone and Convection Zone. The outer layers are the Photosphere, the Chromosphere, the Transition Region and the Corona. IRIS will focus its investigation on the Chromosphere and Transition Region.

A measuring device.   Measuring devices have feet on them to measure distance.

Answer: A) 20 or 21 Explanation: According to Pradeep : 20,21 or 22...(1)According to his brother : not 22....(2)From (1)&(2), the birthday falls on February 20 or 21.

Answer: A) TRUE Explanation: Yes, a square is a rhombus. But a rhombus is not a square unless the interior angles are at right angles.   We know that, a square is a quadrilateral with all sides equal and all the interior angles are 90 deg i.e, at right angles.  Whereas a rhombus is also a quadrilateral with all sides equal but the interior angles are not at right angles. Hence, if the interior angles of a rhombus are all at right angles (90 deg), then it is square.

Answer: A) Pillow Explanation: