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.

A method for providing fault tolerance by using multiple hard disk drives

Squirrels typically build leaf nests in the summer by weaving together small branches they've gnawed off of trees. These nests are lined with grass, moss, leaves and pine needles. Both male and female gray squirrels of all ages participate in building dens.
 

Electrical burns occur principally because of the heat generated by the flow of electrical current through the body.

Burns caused by electricity are divided into three types:

electrical burns,

arc burns, and

thermal contact burns.

Electrical burns can result when a person touches electrical wiring or equipment that is used or maintained improperly.

India's first ever micro-drama festival, named Thespis, was held recently in New Delhi. 

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.