Which equation is used to determine the density of a substance?

Jacob’s four-month-old infant is crying continuously. while jacob’s wife suggests that he pick up the baby, jacob’s mother thinks that picking up the baby each time she cries is bad for the baby. why is jacob’s wife right? a. babies sleep better when carried. b. babies learn to cry whenever they want someone to hold them. c. babies may choke if crying while lying on their back. d. babies develop a sense of trust that someone is there to provide care.