What is mass? O A. The measure of the amount of matter in a substance
B.
the
measure of the amount of matter per unit of volume
C. The measure of the amount of space a substance takes up
D. The measure of the amount of space per unit of volume

Sawyer is studying diffraction. he draws a diagram of a plane wave to show how light waves travel. which best describes sawyer’s error? the wave fronts should be perpendicular to the direction in which the waves move. the arrow showing the direction of movement of the waves should be pointing to the left. the arrow showing the direction of movement of the waves should be pointing downward. the wave fronts should be both parallel and perpendicular to the direction in which the waves move.

Could we see a galaxy that is 20 billion light-years away?

Using the black numbers on the stopwatch to answer the questions. what is the most accurate reading of seconds as indicated by the long second hand? a. 5.3 b. 5.6 c. 7.2 d. 53 secs its for edg i found out it was 5.3 and tenth of seconds freebie