You should ask about admissions standards and about the undergraduate colleges and universities of current graduate students. You should also inquire about the postdoctoral and employment positions of graduates of the institution. Faculty quality is measured in many ways, including their national and international reputations. These reputations are reflected in research publications in peer-reviewed scientific journals, and by the ability of the faculty to compete successfully for research grants and contracts. These measures indicate the degree to which other scientists recognize the research efforts of the faculty.
Scientific research is an expensive enterprise.
The ability of the faculty to secure funds to purchase modern laboratory equipment, information technologies, and other necessities is an indicator of a high-quality research effort. Most students who plan to continue their studies in graduate school apply to several programs. Most programs are highly selective, and a student who applies to only one or two programs may miss out entirely. You should visit the graduate schools that offer you a position before you accept an offer. Your visit should include exploring the program and department making the offer.