Can anyone answer this question from commonlit

If you rub a balloon on a piece of fabric or carpeting and then hold it against your head, your hair can stand on end. use what you have learned in this lesson to explain why this happens.

According to the federal regulations, which of the following studies meets the definition of research with human subjects? a. a researcher uses the customs office’s passenger lists for ships bringing immigrants to the us between 1820-1845 to track the numbers of immigrants from certain ethnic groups. b. a researcher conducts a linguistic study of comments posted on a local public blog. c. a developmental psychologist videotapes interactions between groups of toddlers and their care givers to determine which intervention methods most effectively manage aggression. d. a researcher asks the director of a local free clinic about the number of patients in the last two years with newly diagnosed hiv/aids.

Imagine you are driving down the highway and reading a sign that states save the planet don't litter which technique of policy enactment is being used