The speed of a wave can be calculated by multiplying the frequency by the wavelength. you can also calculate wave speed by dividing wavelength by the period of the wave. why does this make sense?

Answer evaporation and condensation;

Ithink u should look on google

Ithink its a im not sure 

The earth's inner core is the earth's innermost part. it is primarily a solid ball with a radius of about 1,220 km (760 miles), which is about 70% of the moon's radius.[1][2] it is composed of an iron–nickel alloy and some light elements. the temperature at the inner core's surface is approximately 5,700 k (5,430 °c), which is about the temperature at the surface of the sun.