In the illustration of the solar spectrum, the upper left portion of the spectrum shows the visible light. View Available Hint(s) In the illustration of the solar spectrum, the upper left portion of the spectrum shows the visible light. lowest speed brightest highest speed lowest frequency highest frequency.

Red light

Explanation:

The red light is the light with the lowest frequency on the solar spectrum, which invariably means it has the longest wavelength. Frequency is inversely related with wavelength. Therefore, the visible light with low frequencies are found on the left portion of the solar spectrum.

Speed of light, V = wavelength * Frequency.

the area between the graph and the t axis