Explicar cómo se preparan 275gr de una solución acuosa de cetona 3 m/m​

Explain how fossils scientists make discoveries about the lives of organisms and about how environments have changed over time. plz hurry up it time

Which is an advantage of having memory cells when a pathogen is encountered for a second time. a) the memory cells are what proliferate into clones of cells in response to the binding of an antigen. b) memory cells are vital to the primary immune response in that they immediately recognize pathogens even at the first encounter. c) memory cells are essentially effector cells that are short lived and attack antigens even without having a receptor specific to that antigen. d) it ensures that more lymphocytes with a receptor specific to a particular antigen will be present than in a host that had never encountered that pathogen.

Which of the following describes research that would be considered basic science? a. a farmer is trying to improve his crop yields by using a new kind of fertilizer. b. a college students is curious about the growth of desert pants in the presence of excess amounts of water. c. government officials are trying to prevent the spread of new strain of influenza virus. d. a doctor is trying to determine why a patient is feeling tried and sick. b.a college students is curious about the growth of desert pants in the presence of excess amount of water