Question Discussion & Solution

The correct answer is option 3.

Concept:

A semaphore is a variable or abstract data type used to control access to a common resource by multiple threads and avoid critical section problems in a concurrent system such as a multitasking operating system.

Explanation:

Starvation is a problem that happens when high-priority processes continue to run while low priority processes are halted indefinitely. A continual stream of higher-priority processes in a densely loaded computer system can prevent a low-priority operation from ever receiving the CPU.

Indefinite blocking or starvation is a situation in which processes wait indefinitely within the semaphore. Indefinite blocking may occur if we remove processes from the list associated with a semaphore in LIFO (last-in, first-out) order.

Hence the correct answer is starvation.

Additional InformationCritical section:

 The critical section is the section of code in which processes access and write to shared resources such as common variables and files. Because processes run continuously, any process can be interrupted in the middle of its execution.

The correct option is 2 i.e. Sodium Carbonate

Key Points

• Sodium Carbonate is also known as washing soda it is a salt of carbonic acid.
• Sodium carbonate can be manufactured by Solvay's process.
• It is used for treating hard water and industrial detergent mixtures.
• The aqueous solution of sodium carbonate is alkaline.
• Calcium Sulphate exists in the forms of white solids and is not soluble in water.
• Plaster of Paris and Gypsum are its hydrates.

The correct answer is Displacement.

Key Points

•  Displacement
  • When a body moves from one position to another, the shortest distance between the initial position and final position of the body along with direction is known as Displacement.
  • Its SI unit is a meter.
  • It is a vector quantity.
  • Displacement of the object can be positive, negative, zero.
  • Displacement of the object can never be greater than the distance traveled by it.
• When there is no change in an initial position and final position even after covering some path, then it is considered zero displacements.

Additional Information

• Distance
  • It is the actual path covered by a moving body irrespective of the direction in which the body travels.
  • Its SI unit is a meter.
  • It is a scalar quantity.
  • An odometer is used to measure the distance traveled by the vehicle.  
• Speed
  • The time rate of change of position of the object in any direction is called the speed of the object.
  • It is a scalar quantity.
  • Its SI unit is m/s.
  • Speed= Distance travelled/Time taken
• Frequency
  • It tells us how frequently an event occurs.
  • The number of complete waves produced in one second is called the frequency of the waves.
  • Hertz is the SI unit of Frequency. It is named in the honor of Rudolf Hertz.
  • 1 Hertz= 1 vibration per second.

The correct answer is Select, where, group by, having.

Additional Information

Six Operations to Order: SELECT, FROM, WHERE, GROUP BY, HAVING, and ORDER BY. Because the database executes query components in a specific order,

SELECT select_list [ INTO new_table ]  [ FROM table_source ]

[ WHERE search_condition ]

[ GROUP BY group_by_expression ]

[ HAVING search_condition ]

[ ORDER BY order_expression [ ASC | DESC ] ]

Hence Option 4 is correct

The correct answer is Magnesium Sulfate.

• Magnesium Sulfate is the industrial name of Epsom.
• Magnesium sulfate is a magnesium salt having sulfate as the counterion.
• It has a role as an anticonvulsant, a cardiovascular drug, a calcium channel blocker, an anaesthetic, a tocolytic agent, an anti-arrhythmia drug, an analgesic, and a fertilizer. It is a magnesium salt and a metal sulfate.

Key Points

• Magnesium Sulfate Formula Structure:  

Additional Information