Pls help!!Why do scientists use models? Question 1 options:

because some systems are so large, small, or complex they are difficult to predict

all answers are true

to aid in the development of questions and explanations about systems

to replicate and simplify physical reality to allow for precise experiments

In a sample of oxygen gas at room temperature, the average kinetic energy of all the balls stays constant. which postulate of kinetic molecular theory best explains how this is possible? a. attractive forces between gas particles are negligible because the particles of an ideal gas are moving so quickly. b. collisions between gas particles are elastic; there is no net gain or loss of kinetic energy. c. gases consist of a large number of small particles, with a lot of space between the particles. d. gas particles are in constant, random motion, and higher kinetic energy means faster movement.

Melissa is interested in her family tree and how her family has changed over its many generations. melissa probably more closely resembles

Skills of homo sapiens were found an excavation. the skulls were preserved because the bodies were frozen. so, these fossils are (blank) fossils.the image shows the evolution of skulls beginning 2 to 3 million years ago. based on the image, modern human skulls(blank) ape skulls.