Plz helpA student heard the echo of her voice from nearby solid object after 2 sec. how far away is the solid object? The speed of sound in air is 340m/s. A. 170m

B. 340m

C. 510m

D. 680m

Which statement is true for light passing into a medium that is more optically dense than the first medium through which it past

If a balloon is taken outside on a very cold day, what will occur?

Need people build a dam to create a reservoir that supplies water a nearby city needs. describe two ways this action will likely affect the water cycle in the local environment. (5 points) worth 20 points