Respuesta :

Answer:

17

Step-by-step explanation:

because 19 students for the other in total (you add the ones who study biology and the ones who study both, then you minus the group of students by 19)

Answer:

21

Step-by-step explanation:

this is really easy so what you do is

you know 13 study bio and NOT art

we also know 2 student study neither subject

so lets just do 36-15

which is 21, this 21 does include the 6 that study both and the rest we can safely assume study art