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The correct answer is Phosphine.

Key Points

• Phosphine smells like rotting fish.
• Phosphine is a toxic, flammable gas.
• It is often associated with a foul odor similar to that of decaying fish.
• Phosphine is used in various industrial applications but is highly hazardous.
• It is important to handle phosphine with care due to its toxic properties.

Additional Information

• Ozone has a distinct sharp smell, often described as similar to chlorine.
• Chlorine has a strong, pungent smell often associated with bleach.
• Acetylene gas has a garlic-like odor.

Shortcut Trick

Efficiency Ratio (A : B) = 3 : 1 ⇒ Time Ratio (A : B) = 1 : 3.

Difference in time units = 3 − 1 = 2 units.

Given 2 units = 16 min ⇒ 1 unit = 8 min (Time for Pipe A) and 3 units = 24 min (Time for Pipe B).

Combined time = (A × B) ÷ (A + B) = (8 × 24) ÷ (8 + 24) = 192 ÷ 32 = 6 min.

∴ The correct answer is 6 min.

Alternate Method

Given: Capacity of Pipe A is thrice that of Pipe B. Time difference between A and B to fill the tank is 16 min.

⇒ Let Efficiency of Pipe B = 1 unit/min. Then Efficiency of Pipe A = 3 units/min.

⇒ Let Time taken by Pipe B = t min. Time taken by Pipe A = (t − 16) min.

⇒ Since Total Work is constant: Efficiency_A × Time_A = Efficiency_B × Time_B

⇒ 3 × (t − 16) = 1 × t ⇒ 3t − 48 = t ⇒ 2t = 48 ⇒ t = 24 min.

⇒ Combined Efficiency (A + B) = 3 + 1 = 4 units/min.

⇒ Time taken together = Total Work ÷ Combined Efficiency = 24 ÷ 4 = 6 min.

∴ The correct answer is 6 min.

Additional Information

Efficiency and Time Relation

For a fixed work, Efficiency is inversely proportional to Time. If efficiency ratio is a:b, then time ratio is b:a.

Combined Work Formula

If two pipes can fill a tank in x and y minutes respectively, then both together can fill it in (xy) ÷ (x + y) minutes.

Work-Efficiency Product

Total Work = Efficiency × Time. This constant product helps in establishing equations between different pipes.

The correct answer is Jyotiba Phule.

Key Points

• Jyotiba Phule founded the Satyasodhak Samaj in 1873.
• The main objective of the Satyasodhak Samaj was to achieve social justice and to provide equal rights to the underprivileged sections of society.
• Jyotiba Phule was a prominent social reformer and activist who worked towards the upliftment of women and lower castes in India.

Additional Information

• Jyotiba Phule, along with his wife Savitribai Phule, was a pioneer in women's education in India.
• He also fought against the caste system and untouchability, advocating for the rights of oppressed classes.
• The Satyasodhak Samaj's principles were based on human rights, dignity, and social justice.

The logic followed here is:

 

All of the options are the pair of secondary colors, 

Whereas,

Blue - Red are the primary colors.

Hence, the correct answer is "Option 4".

Important Points

The correct answer is 2.

Key Points

• Humans have a total of 46 chromosomes in each cell, arranged in 23 pairs.
• Among these 23 pairs, one pair is the sex chromosomes.
• Females have two X chromosomes (XX).
• Males have one X and one Y chromosome (XY).
• Sex chromosomes determine the biological sex of an individual.

Additional Information

• Autosomes are the other 22 pairs of chromosomes that are not sex chromosomes.
• These chromosomes contain the bulk of an individual's genetic information.
• Chromosomes are structures within cells that contain DNA and many genes.
• They play a crucial role in heredity and the functioning of cells.

According to the given information,

1) A man is facing towards West and turns through 45° clockwise.

2. Again turns 180° clockwise.

3. Then turns through 270° anticlockwise.

Here, we can see that he is now facing southwest direction.

Hence, the correct answer is "Southwest".

The correct answer is Asmaka.

Key Points

• Asmaka was one of the sixteen Mahajanapadas mentioned in ancient Indian texts.
• It was located in the southern part of India, specifically in the region that is now part of Maharashtra and Andhra Pradesh.
• The capital of Asmaka was Potali or Podana, which is identified with modern-day Bodhan in Telangana.
• The Mahajanapadas were a set of sixteen kingdoms or oligarchic republics that existed in ancient India from the 6^th to 4^th centuries BCE.

Additional Information

• The other Mahajanapadas were primarily located in the northern and eastern parts of India.
• Koshala and Anga were located in the northern region, while Malaba is not recognized as one of the sixteen Mahajanapadas.
• The Mahajanapadas played a crucial role in the political and cultural development of ancient India.

The logic followed here is:

Logic: The terms of the series are the resultant of consecutive prime numbers + 1.

Hence, the correct answer is "32, 38".

The correct answer is Niels Bohr.

Key Points

• Niels Bohr explained the structure of the atom using Quantum Theory.
• Quantum Theory describes the behavior of particles at the atomic and subatomic levels.
• Bohr's model introduced the idea that electrons orbit the nucleus at specific distances.
• This model was a significant advancement in understanding atomic structure and laid the groundwork for modern quantum mechanics.

Additional Information

• Other notable scientists:
• Oppenheimer: Known for his role in the Manhattan Project.
• Albert Einstein: Developed the theory of relativity.
• Rutherford: Known for the gold foil experiment and the discovery of the nucleus.
• Bohr's contributions:
• He received the Nobel Prize in Physics in 1922 for his work on the structure of atoms.
• Bohr's work helped to explain the periodic table and the chemical behavior of elements.

Given:

A's capacity to complete a work is thrice that of B.

A completes the work 20 days prior to B.

Formula Used:

Work Done = Capacity × Time

When working together, combined capacity = Sum of individual capacities

Time = Work / Combined capacity

Calculation:

Let B's capacity be x.

Then, A's capacity = 3x.

Let B takes T days to complete the work.

⇒ A takes (T - 20) days to complete the work.

Since Work Done = Capacity × Time:

B's work done = x × T

A's work done = 3x × (T - 20)

Since both are completing the same work:

⇒ x × T = 3x × (T - 20)

⇒ T = 3(T - 20)

⇒ T = 3T - 60

⇒ 2T = 60

⇒ T = 30

So, B takes 30 days, and A takes 10 days to complete the work.

Combined capacity = x + 3x = 4x

Let total work be W. Then W = x × 30 = 30x.

Time taken to complete the work together:

⇒ Time = Work / Combined capacity

⇒ Time = 30x / 4x

⇒ Time = 30 / 4

⇒ Time = 7.5 days

They can complete the work together in 7.5 days.