Final answer:
About 70% of incoming solar radiation is absorbed by Earth after accounting for the 30% that is reflected. However, analysis and options provided in the question do not accurately represent the percentage hitting the surface directly due to the averaging effect over Earth's entire surface area.
Step-by-step explanation:
The percentage of light that hits Earth's surface directly is not explicitly given as an exact figure in the options provided. However, we know from the information provided that about 30% of the incoming solar radiation of 1,360 W/m² is reflected back into space, primarily by clouds, snow, and other reflective surfaces. This leaves approximately 70% to be absorbed by Earth. Furthermore, considering that the Earth's surface area is four times the projected area which intercepts the sunlight directly, this implies that the averaged absorption rate over the entire surface is reduced. Therefore, when accounting for reflection and distribution over the entire surface, none of the options (3%, 5%, 31%, 47%) accurately describes the percentage of light hitting Earth's surface directly. The value would be less than 70% after accommodating the reflection and spherical distribution factors.