Explanation

The first open-heart surgery in India was performed on February 16, 1961

By Dr. K.N. Dastur at BYL Nair Hospital in Mumbai.

He used a heart-lung machine developed with the help of engineers at the National Steel Company.

The surgery was performed on a 19-year-old girl named Hemlata 

Explanation

Handheld metal detectors commonly use batteries ranging from 1.5V (AA) up to 9V.

This low voltage powers the device for portability and safety.

Explanation

Provisional security refers to local or regional security arrangements, typically handled by the District Police.

Customs deals with border control and goods regulation.

Explanation

A path is a little road (often so small that only one person can use it at a time),

while a highway is a large road with room for thousands.

A brook and a river have a similar size relationship.

Explanation

Armistice ended fighting of: Ottoman Empire and the Allies

Held: October 1918

Explanation

 The world's first public airline was DELAG (Deutsche Luftschiffahrts-Aktiengesellschaft),

It was founded on November 16, 1909, with government support

Its headquarters is in Frankfurt

DELAG, meaning "German Airship Navigation Company,"

Explanation

Suleiman the Magnificent invaded Vienna in 1529, during the first siege of Vienna.

This siege, which lasted for just over two weeks (September 27 to October 15, 1529)

Explanation

Many handheld metal detectors commonly use 9V batteries, and their operating voltage often falls within the 6V-9V range.

Some sources might mention a lower range like 3-5V for simpler detectors, while others specify a slightly higher range like 7-9V. 

Explanation

"On" is used for specific dates (e.g., "on 23rd June").

"In" is for months/years (e.g., "in June").

"At" is for precise times (e.g., "at 9 AM").

Explanation

The Gawadar International Airport was constructed under the China-Pakistan Economic Corridor (CPEC).

It is the largest airport in Pakistan by area

Occupying 4,300 acres (17 km2) of land

Opened 20 January 2025