Question

a heavy curtain is ______ because it does not let any light pass through into the room.
you can see your face in a calm pond because of ______ off the waters surface.
a pencil looks bent in a cup of water because of ______ when light moves from water into air.
radio and x - ray waves are both types of ____ ____ that travel through space without needing air.
when a loud drum is hit harder, the ______ of the sound wave increases so the drum sounds louder.
when measuring ripples from a dropped pebble, the distance between two consecutive crests tells you the ______ of the wave.
____ ____ are not valuable in space because they require a medium
frequency amplitude wavelength electromagnetic waves translucent opaque
transparent refraction reflection rarefaction diffusion

Explanation:

First Question:

A heavy curtain that doesn't let light pass through is opaque (materials that block light completely, unlike transparent/translucent which allow some or all light through).

Second Question:

Seeing your face in a calm pond is due to light reflecting off the water's surface (reflection is the bouncing back of light).

Third Question:

A pencil looks bent in water because light bends (refracts) when moving from water (denser medium) to air (less dense medium).

Fourth Question:

Answer:

opaque