The correct answer is c, it’s evaporating there for it’s a chemical change
Started out as some other type of rock, but have been substantially changed from their original igneous, sedimentary, or earlier metamorphic form. Metamorphic rocks form when rocks are subjected to high heat, high pressure, hot mineral-rich fluids or, more commonly, some combination of these factors.
Answer:
A population or community research line can be carried out, wherever at a certain point in time, regardless of whether it is a cross-sectional study.
In addition, the people who would be the population to be studied or the object of study might or might not know the cause of the study (blind) while the researcher could be experimentally participatory.
Explanation:
They are prevalence studies, in which the presence of a health condition or state is determined in a well-defined population and in a determined time frame: one day, one week, a particular moment in life, even if it does not temporarily coincide in all the subjects (for example, the blood pressure figures at the time of entering the school or at the beginning of the holidays, the prevalence of diabetes in hospitalized patients on a given day, etc.).
They are like "photographs" of a state of affairs at a given moment. The simultaneous determination of what is understood by exposure and event does not allow defining causality.
The question is incomplete, here is the complete question:
Write a balanced chemical equation for each single replacement reaction that takes place in aqueous solution. write no reaction if a reaction does not occur
1.) Zn + PbCl₂
2.) Cu + Fe(NO₃)₂
<u>Answer:</u>
<u>For 1:</u> The reaction does occur.
<u>For 2:</u> The reaction does not occur.
<u>Explanation:</u>
Single displacement reaction is defined as the reaction in which more reactive element displaces a less reactive element.
The reactivity of metal is determined by a series known as reactivity series. The metals lying above in the series are more reactive than the metals which lie below in the series.

For the given options:
Zinc is more reactive than lead as it lies above in the series. So, it will displace lead from its chemical equation.
The chemical equation for the reaction of zinc and lead chloride follows:

Copper is less reactive than iron as it lies below in the series. So, it will not displace iron from its chemical equation.
The chemical equation for the reaction of copper and iron (II) nitrate follows:
