Answer: A) TRUE Explanation: Milk is converted into curd or yogurt by the process of fermentation. Milk consists of globular proteins called casein.    It is biochemical change because here microorganism named lactobacillus react with milk and turn it to curd. Lactobacillus required favourable condition to grow. For it 37 degree temperature is needed. But sometimes when it does not get favourable condition, then other microorganism react and makes the curd taste different.

Answer: C) Sister Explanation:

Answer: D) 500 mts Explanation: Using pythagarous theorem,distance travelled by first train = 36x5/18x30 = 300mdistance travelled by second train = 48x5/18x30 = 400mso distance between them =√( 90000 + 160000) = √250000 = 500mts.

Answer: D) 120 sq.cm Explanation: The triangle with sides 26 cm, 24 cm and 10 cm is right angled, where the hypotenuse is 26 cm. Area of the triangle =1/2 x base x height => 1/2 x 24 x 10 = 120 sq.cm

Answer: D) 100% Explanation: When 3 passengers income was 3xexpense= Rs.30 profit =20% of 30 = Rs.6 That means his earning is Rs.36. so that per passenger fare must be Rs.12. When 4 passengersearning = 12x4=Rs.48.expense =Rs.24.profit = Rs.24 = 100%

Answer: C) Thunder Explanation: The Sound Following the flash of lighting is because of Thunder.   Lightning is seen earlier than thunder because light travels much faster than sound.   The roar of thunder is the result of a shock wave produced when lightning super-heats the air through which it passes, causing that air to expand very rapidly. This rapid expansion of air creates a shock wave that travels outward at close to the speed of sound.

Answer: C) rapid spring snowmelt Explanation: There are lots of reasons behind the flood in any area but the main reason is a heavy downpour or rapid snowmelt can flood canyons with a mixture of soil, rock, and water is a major cause of floods.   When the spring times come, sometimes there's a lot of warmth that suddenly comes, especially nowadays when there are things such as global warming. So the snow melts and large amounts of water can flood the fields that are often found at the foot of a mountain or similar things.   But they may also be caused by deforestation, drainage channel modification from a landslide, earthquake or volcanic eruption. Examples include outburst floods and lahars.

Answer: B) key : piano Explanation: A bristle is a part of a brush; a key is a part of a piano.