Cho a, b,c là ba số thực thỏa mãn a, b>0 và a+b+c=1. Chứng minh rằng a) (a+b)*(a+c)=a+bc

b) =a+b

Abby is preparing fruit punch for her party. she starts with a bowl filled with liquid that has 1/2 fruit juice and 1/2 sprite, but she decides it's too fruity. so she pours out 1/4 of the liquid, and then fills the bowl up again with sprite. what fraction of the punch is now sprite?

Can someone me and do the problem plz so i can understand it more better

The american academy of pediatrics wants to conduct a survey of recently graduated family practitioners to assess why they did not choose pediatrics for their specialization. provide a definition of the population, suggest a sampling frame, and indicate the appropriate sampling unit.