Intermittent activity means participating by paying attention developing a skill focusing on what you are hearing taking in sounds

None of the options is correct.

INTERMITTENT ACTIVITY means that you perform said activity at irregular intervals, in a sporadic way. On the contrary, the options mentioned require the subject to participate actively. For example, in order to develop a skill it is important to practice a lot. In the same way, if you focus on what you are hearing, you are paying attention which is the opposite to what an intermittent activity is.

participating by paying attention

Explanation:

The word "intermittent" is a term that is commonly used to describe an activity where the physical exertion is taking place. This is a phrase that is used to describe a variety of the training routines that are followed throughout a physical activity. The term "intermittent" also means the stop and start intervals. Because the activity is a start and stop activity, it requires high levels of attention to detail.

answer: in 1900, there were no "workplace safety laws"!

explanation: at the beginning of this century, workers in the united states faced remarkably high health and safety risks on the job.

a century ago in 1900 about three hundred out of every one hundred thousand miners were killed on the job each year.

[industria] developments occurred within a legal and regulatory climate that diminished employer’s interest in safety. as a result, americans developed production methods that were both highly productive and often very dangerous.

the answer is a. the harappan civilisation is also called the indus valley civilisation, this is because they built their cities along the indus river. the reason behind this location can be found in the rest of the "old world" civilisations like mesopotamia or egypt, the first built their cities along the rivers tigris and euphrates, the second along the nil; : their respective civilisations thrived because the overflowing of their respective rivers produced favorable conditions for agriculture, their main support.