One nanometer is equal to how many centimeters

Heat from the sun reaches earth to a. radiation b. convection c. conduction

Wo audio speakers are placed on a vertical rail. speaker a is placed at head-level while speaker b is place at some variable height, \delta yδy, above speaker a. both speakers receive simultaneous input from a sine-wave generator so the speakers each produce a pure sinusoidal sound wave with a wavelength of 0.531 meters. calculate the lowest height that speaker b can be placed above speaker a to produce a minimum of sound heard by person standing \delta x = 7.86δx=7.86 meters directly in front of speaker a.

How much energy must a refrigerator absorb from 225 g of water so that the temperature of the water will drop from 35°c to 5°c