The moon appears half lit, half dark from the surface of Earth on two days each month. What causes this? (1 point) Half of the moon's surface that is illuminated by the sun is visible from Earth's perspective.

Earth’s shadow is blocking the light from the sun.

Half of the moon is totally eclipsed.

It is a partial lunar eclipse.

Even though the ostrich is a flightless bird, ostriches still possess wings that stretch approximately two meters across when fully extended. scientists speculate that when dinosaurs became extinct, some of the birds that lived during that time became land dwellers since they were able to consume the food that the dinosaurs once ate. over time, these species grew larger and heavier. eventually, the ostrich species became too big to fly. the wings found on ostriches are known as a. analogous structures. b. homologous structures. c. vestigial structures. d. symmetrical structures.