7. For radio reception, diffraction is . a. helpful
b. a hindrance
c. cannot tell its effect
d. not a factor

Plz will mark! the diagram shows the positions of the sun, moon and earth during spring tides, when the high tides are at their highest and low tides at their lowest. what is it about these positions that causes these high and low tides?

Apaleontologist finds a plant fossil that shows that the plant had seeds. what can the paleontologist conclude?

Drag each description to the correct location on the image. not all descriptions will be used. describe the parts of a comet. the frozen part of the comet the atmosphere of gases and dust formed when the nucleus vaporizes tail made of small, solid dust particles tail made of ions that appears to point away from the comet's orbit