Answer: C) forest improving to deserts Explanation: Desertification is a type of land degradation in which a relatively dry area of land becomes increasingly arid, typically losing its bodies of water as well as vegetation and wildlife.   Conversion of a grassland or an already arid land into a desert through indiscriminate human actions magnified by droughts.   Hence, forest improving to deserts is refers to desertification.

Answer: C) 7 & 24 Explanation: 7 boxes & 24 Balls.Let, n = No. of boxes ; m = No. of fruits3n+3 = m---------->(1)4(n-1)= m---------->(2)=>4n-4 = 3n+3;=>4n-3n = 4+3n = 7Put n=7 in eqn(1)=> 3(7)+3 = m21+3 = mm = 24; Number of boxes = 7 and fruits = 24

An organelle called Eyespot allows some protists to detect light. It allows the cells to sense light direction and intensity and respond to it by swimming either towards the light (positive phototaxis) or away from the light (negative phototaxis).   Eyespot is a photoreceptive organelle found in the flagellate or (motile) cells of green algae and other unicellular photosynthetic organisms such as euglenids.   Eyespot-mediated light perception helps the cells in finding an environment with optimal light conditions for photosynthesis. Eyespots are the simplest and most common "eyes" found in nature, composed of photoreceptors and areas of bright orange-red pigment granules.

We know that polar substances are soluble in polar solvents and non polar substances are soluble in non-polar solvents only. Here the hydrocarbons are non-polar molecular substances and water is a polar solvent. So water can't dissolve hydrocabons.   Hence, as hydrocarbons are non-polar substances, they are insoluble in water as it is a highly polar solvent.

Answer: D) 248 yrs Explanation: It takes 248 yrs for Pluto to orbit the Sun.

Answer: D) a > b Explanation: From solving 1 and 2 we get,   1. 5a(a-3)-3(a-3) = 0   (5a-3)(a-3) = 0   a = 3 or 3/5   2.    3b(b+2)-1(b+2) = 0   b = -2 or b = 1/3   Here when a = 3, a > b for b = -2 and b = 1/3   when a = 3/5. a > b for b = -2 and b = 1/3.   Hence, it is clear that a > b.

Answer: C) Ram Nath Kovind Explanation: BJP-led NDA's presidential candidate Ram Nath Kovind registered an emphatic win over his rival and Opposition candidate Meira Kumar. Succeeding Pranab Mukherjee, Kovind sworn in as the 14th president of India on July 25, 2017.

Answer: C) 192 Explanation: Let the third subject marks be 'x'=> Second subject marks = 2x=> Third subject marks = 4xGiven avg = 224x + 2x + 4x = 224 x 3=> 7x = 224 x 3=> x = 96Hence, Second subject marks = 2x = 2 x 96 = 192.