Will mark brainliest. What is the main function of the circulatory system in multicellular organisms? A: to bring oxygen into the lung.

B: to put carbon dioxide into all the blood vessels.

C: to expel waste products from the body.

D: to transport materials through the body.

The rules of engagement (roe) working group is often used to (select all that apply.)

How do i turn 2 s into one in the products

Answer asap need to be answered by wednesday morning explain how a buffer works, using an ethanoic acid / sodium ethanoate system including how the system resists changes in ph upon addition of a small amount of base and upon addition of a small amount of acid respectively. include the following calculations in your i. calculate the ph of a solution made by mixing 25cm3 0.1m ch3cooh and 40cm3 0.1m ch3coo-na+. [ka = 1.74 x 10-5 m] ii. calculate the ph following the addition of a 10cm3 portion of 0.08 m naoh to 500cm3 of this buffer solution. iii. calculate the ph following the addition of a 10cm3 portion of 0.08 m hcl to 200cm3 of the original buffer solution.