Consider the hydrocarbon below. 2 carbons are double-bonded to each other; the pair are single bonded to H above left, above right, below right, and below left. What is the name of this hydrocarbon?

Ethene.

Explanation:

To know the name of the compound given above, we must:

1. Determine the number of carbon present in the compound.

2. Determine whether a single, double or triple is present in the compound.

3. Combine the above to get the name.

Now, let us name compound given above. This is illustrated below:

1. The compound contains two (2) carbon atom.

2. The compound contains a double bond. Therefore, the compound is an alkene.

3. An alkene with two carbon atoms is called ethene.

Therefore, the name of the compound given in the question is called ethene.

c. because step up transformer steps up the input voltage i.e increases the input voltage  

the number of turns are greater on the secondary side of step up transformer  

transformer does not handle dc current

the mantle

explanation:

earth is divided into three layers: the crust or the outermost layer on which we live; the underlying, middle layer - the mantle - and the core (the innermost layer of earth).