Answer: C) cosx Explanation:   Thus, the derivative of sinx by first principle is cosx.

Answer: B) HSBC Bank Explanation: HSBC (Hongkong and Shanghai Banking Corporation) is the first bank to introduce ATM concept in India in the year 1987 in Mumbai.

Photoautotrophs are those organisms that can make their own food using sun light with the help of the process of photosynthesis. Plants can prepare their own food using sunlight. Hence they are Photoautotrophs.

Answer: C) 71 Explanation: To find the greatest number which divides the numbers 964, 1238 and 1400 leaving the remainders 41, 31 and 51 is nothing but the HCF of (964 - 41), (1238 - 31), (1400 - 51). Therefore, HCF of 923, 1207 and 1349 is 71.

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: A) 84 km/hr Explanation: Let the speeds of the car, train and bus be 5x, 9x and 4x km/hr respectively.Average speed = 5x + 9x + 4x/3 = 18x /3 = 6x km/hr.Also, 6x = 72 => x = 12 km/hrTherefore, the average speed of the car and train together is = 5x+9x2= 7x = 7 x 12 = 84 km/hr.

Answer: B) 50540 Explanation: Given G + B= 41 and B = G-1 Hence, G = 21 and B = 20Now we have 2 options, 1G and 3M (or) 3G and 1M(2G and 2M or 0G and 4M or 4G and oM are not allowed),   Total : C121×C320+C321×C120= 50540 ways.

Answer: D) 96 Explanation: Here in the given number puzzle, the given numbers follows a pattern that  1 + 4 = 5 => 1 x 4 + 1 = 4 + 1 = 5  2 + 5 = 12 => 2 x 5 + 2 = 10 + 2 = 12    3 + 6 = 21 => 3 x 6 + 3 = 18 + 3 = 21  Similarly,  8 + 11 = 96 => 8 x 11 + 8 = 88 + 8 = 96   Hence, the missing number in the given number puzzle is 96.