Questions

• Cactus spines are also known as modified bud scales, which are also called modified leaves.

• Cactus spines occur in clusters in the axil of leaves.

B.R. Ambedkar

Sukhna Lake is in Chandigarh, India.

It is a reservoir at the foothills of the Himalayas. It covers an area of 3 km². This rainfed lake was created in 1958 by damming the Sukhna Choe, a seasonal stream coming down from the Shivalik Hills.

You have to consider three things.

1. First, are the bonds polar?

Look at differences in electronegativity and if  it is >0.5, bonds are polar.

2. Second, does the molecule have unshared electron pairs?

If so, they generally lead to a polar molecule.

3. Third, is the molecule symmetric?

If so, then although the bonds may be polar, the symmetry cancels out the individual bond polarity and the molecule is non polar.

CF4 follows all the rules above and has a symmetric distribution of charge, making it nonpolar. The others all have asymmetric charge distributions.

Hence, CF4 represents a Non-polar molecule.

IPCC stands for the Intergovernmental Panel on Climate Change. It was established in 1988 by the World Meteorological Organization and the United Nations Environment Programme.

• IPCC, with respect to Chartered Accountancy, stands for Integrated Professional Competence Course. This is the second level of the CA course.

In a brief, the system software is the interface between the hardware and user applications. System software is a type of computer program that is designed to run a computer’s hardware and application programs.

Examples : OS, System utilities, BIOS like mouse, keyboard, hard disc, Device drivers, Assembler,...