Questions

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.

There are many isotopes of uranium and all of them have same atomic number i.e, sum of nmber of neutrons and protons.

The world's tallest twisted tower, the Infinity Tower was launched in Dubai Marina on 10 June 2013.

The doctrine of the subsidiary alliance was introduced by Lord Wellesley, British Governor-General of India from 1798 to 1805.

The Nizam of Hyderabad was the first to enter into such an alliance in 1798. Tipu Sultan of Mysore refused to do so, but after the British victory in the Fourth Anglo-Mysore War, Mysore was forced to become a subsidiary state in 1799.

The Nawab of Awadh was the next to accept the Subsidiary Alliance, in 1801.

The nearest stars to Earth are in the Alpha Centauri triple-star system, about 4.37 light-years away. One of these stars, Proxima Centauri, is slightly closer, at 4.26 light-years.

Of all the stars closer than 15 light-years, only two are spectral type G, similar to our sun: Alpha Centauri A and Tau Ceti. The majority are M-type red dwarf stars.

Only nine of the stars in this area is bright enough to be seen by the naked human eye from Earth. These brightest stars include Alpha Centauri A and B, Sirius A, Epsilon Eridani, Procyon, 61 Cygni A and B, Epsilon Indi A and Tau Ceti.

A modem is nothing but short for Modulator and Demodulator. It is used mostly for connecting to the internet.

A modem is a device or program that enables a computer to transmit data over, for example, telephone or cable lines. Computer information is stored digitally, whereas information transmitted over telephone lines is transmitted in the form of analog waves.