A fixed resistor, (R) is in parallel with a variable resistor; both are connected to a real battery (internal resistance is not negligible). A) Originally the fixed and variable resistors have the same resistance. (b) As the resistance of the variable resistor is decreased, the rate at which energy is transferred to the fixed resistor

decreases

Explanation:

Energy in a resistor= I²R

According to ohms law, V=IR

Inititally current through both the resistors is same. When resistance of variable resistor is decreased, current through it increases and less current flows through fixed resistor. Consequently energy dissipated in fixed resistor also decreases.

scattering of light by tiny particles in air to produce the colors we see on sky, is dependent on the following factors:

(i) wavelength of light

(ii) size of the scattering particle  

(iii) distance traveled by light through the atmosphere.

according to rayleigh's law of scattering, the amount of scattering is inversely proportional to the fourth power of its wavelength. shorter the wavelength, greater is its scattering. hence violet/blue light is scattered more than red.

sun's light is a composite light ( visible light) with wavelengths in the range 400 nm (violet) to 700 nm (red). as sunlight passes through our atmosphere, the molecules of air scatter light according to their wavelengths. during sunrise and sunset, the sun's position is below the horizon. hence light from the sun travels a greater distance in the atmosphere when compared to its position a noon.

as sunlight enters the earth's atmosphere, blue light is scattered away and at the end of its journey in the sky, only red and orange wavelengths remain in the beam.

hence at sunrise and sunset, the sky appears reddish orange.