The angle of elevation from a point P of the top of a tower QR, 50 m high is 60^o and that of the tower PT from a point Q is 30^o. Find the height of the tower PT, correct to the nearest metre.

Carbon monoxide is dangerous when inhaled.

Name the Indian soil which is formed due to the weathering of basic igneous rocks.

Name the gas evolved in each of the following cases:

1. Alumina undergoes electrolytic reduction.
2. Ethene undergoes hydrogenation reaction.
3. Ammonia reacts with heated copper oxide.

Name the gas that is produced in - Reaction of ethanol and sodium

With reference to the Union Legislature, answer the following questions:

1. Explain any three Legislative powers of the Union Parliament.
2. State any three exclusive powers of the Lok Sabha that is not enjoyed
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Answer the following questions with respect to the electrolytic process in the extraction of aluminum:

1.  Identify the components of the electrolyte other than pure alumina and the role played by each.
2.  Explain
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The model of a building is constructed with the scale factor 1 : 30.

1. If the height of the model is 80 cm, find the actual height of the building in meters.
2. If the actual volume of a tank at the top
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Give reasons for the following: During the day:

1. Clouds appear white.
2. Sky appears blue.

Draw an electron dot diagram to show the formation of each of the following compounds:

1. Methane
2. Magnesium Chloride [H = 1, C = 6, Mg = 12, Cl = 17]

State two characteristics of a good thermion emitter

How do trees in the Tropical desert forests adapt themselves to the dry climate?

The energy required to remove an electron from a neutral isolated gaseous atom and convert it into a positively charged gaseous ion is called ______ . (electron affinity, ionisation potential,...

In Mendel’s experiments, tall pea plants (T) are dominant over dwarf pea plants (t).

1. What is the phenotype and genotype of the F₁ generation if a homozygous tall plant is crossed with a homozygous
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Pulmonary semilunar valve

Mention the exact location of the following:

1. Name the waves used for echo depth sounding.
2. Give one reason for their use for the above purpose.
3. Why are the waves mentioned by you not audible to us?