Questions

CF4 is tetrahedral.

Since the four 'F' atoms have the same electronegativity values, there is no bias in electron distribution toward any one.

Therefore, electron/charge distribution is symmetrical, which also means that the molecule is nonpolar.

Hence, CF4 is nonpolar molecule with a symmetrical distribution of charge.

Tips :

Integrity-being honest and believability and conviction- is one of concrete leadership abilities. The value and morals in personal behavior are the necessaries with an excellent leader and these values and morals need to be brought into organizational training and activities. A successful leader is the one who uses his/her conviction most efficiently. Leaders do not loose confidences or expose potentially dangerous information if they are close with their employees and they are the honest symbols.

We know that, Elements in the same group of the periodic table have similar characteristics.

Here Magnesium and Strontium shared some similar properties because they both belong to the same group. Sr is the chemical symbol for strontium which is a group two element; it has atomic number of 38. 

Patanjali

A fire grows when it eats but dies when it drinks.