Explanation

Tungsten is commonly used as the target material in X-ray tubes due to its high atomic number and ability to withstand the high heat generated during X-ray production.

Its properties make it efficient in producing X-rays.

Explanation

The Basic Education Scheme aims to provide fundamental education to meet the basic needs of individuals.

It ensures access to essential learning for personal and social development.

Explanation

The citizens of FATA (Federally Administered Tribal Areas) were granted the right to vote in 1997 general elections.

Before this, only Maliks (tribal elders) had voting rights under a limited franchise system.

Explanation

In 1961, under Ayub Khan’s regime, the Muslim Family Laws Ordinance was introduced.

It made registration of marriages compulsory in the Union Council to maintain official records and prevent disputes.

Explanation

The respiratory system is responsible for supplying oxygen to the blood and removing carbon dioxide from the body.

Key organs include the lungs, trachea, and diaphragm, which help in breathing and gas exchange.

Explanation

To find when both grades visit the lab on the same day again, we need to find the Least Common Multiple (LCM) of 16 and 30.

Multiples of 16: 16, 32, 48, 64, 80, 96, 112, 128, 144, 160, 176, 192, 208, 224, 240

Multiples of 30: 30, 60, 90, 120, 150, 180, 210, 240

The LCM of 16 and 30 is 240.

Explanation

Child Centered Learning focuses on the interests, needs, and developmental level of the child.

It promotes active participation, exploration, and self-directed learning.

Explanation

At Pre-structural level, students gather unrelated facts with no clear understanding of how they fit together.

Information lacks organization and doesn’t contribute to building a deeper understanding.

Explanation

Oxygen has 8 protons and typically 8 neutrons, giving it a mass number of 16.

Mass number = Number of protons + Number of neutrons.

Explanation

The idiom "flogging a dead horse" means trying to continue with something that has no hope of success.

In this context, it suggests further appeals are pointless and a waste of time.