Which invertebrates are generally small, allowing them to live on little food and hide from enemies? (Hint: invertebrates do not have a backbone) PLEASE HURRY

the correct answer is 2 and 4

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.