Which is the best reason that a geologist might carry a small dropper bottle filled with hydrochloric acid
when doing fieldwork?
to wash rock samples to make them easier to study
to wear away large areas of rock to see what is underneath
to test for the presence of carbonate minerals in a rock
to use as an emergency eyewash in case rock dust gets in the eyes

C, to test for the presence of carbonate minerals in a rock

Explanation:

I did this a few weeks ago on Edge. Hydrochloric acid isn't for rock washing, they wouldn't use it to wear away rocks since it'd ruin the sample I think, and you will go blind if you put it in your eyes

in the year 2850, humans successfully colonized mars. the martian modules that were constructed could hold only a small population of people. it is now a century later, and the population on mars has grown to 600 people. of the current mars population, 45 people express the recessive phenotype for phenylketon- uria (pku) syndrome (pp genotype).

explanation: