Susan has been assigned to build a model of a plant cell. She has many materials to help her build her model: plastic wrap, a plastic sandwich bag, aluminum foil, different kinds of dry pasta, stiff cardboard, and pipe cleaners.
She selects the stiff cardboard to represent which outside supporting part of the plant cell?
O A. cell membrane
O B. mitochondria
O c. cell wall
D. nucleus
E. vacuole

HELP!

i believe the answer is c, cell wall^^

blood enters the heart through two large veins, the inferior and superior vena cava, emptying oxygen-poor blood from the body into the right atrium of the heart. as the ventricle contracts, blood leaves the heart through the pulmonic valve, into the pulmonary artery and to the lungs where it is oxygenated.

propane is burned to provide the heat in many cooking grills. the chemical reaction for this process is shown in the equation below.

c3h8 + 5o2 ? 3 co2 + 4h2o + energy

what are the products in this chemical reaction?

3co2 + 4h2o + energy