What kinds of diseases can vaccinations prevent? genetic diseases only

bacterial diseases only

viral diseases only

any infectious disease

Which of these serves as a reference for comparison during a scientific investigation? a)outcome variable (dependent variable) b) test variable (independent variable) c)control group d)hypothesis

I’m doing some practice exam questions for biology, and i’m not sure how to do these 3 parts to the question.

Which number represents a basic ph, 4 or 9? numerical answers expected! answer for blank 1: i'll give