Which of the following must be true if a sponge is an animal? 1.Sponges eat other organisms
2.Sponges make their own food
3.Sponges move all the time
4.Sponges have a backbone

it is between 1 and 2

Explanation:

Sponges are similar to other animals in that they are multicellular, heterotrophic, lack cell walls and produce sperm cells. ... All sponges are sessile aquatic animals, meaning that they attach to an underwater surface and remain fixed in place (i.e., do not travel).

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.

straight probes are used primarily for measuring flow as it is approaching the test area. its geometry allows the probe to be mounted so that it is in the direct line of airflow.