Why do the poles receive less solar radiation than the equator?

It is because the North and South Poles don't point right at the Sun, as the Equator does, being on the top of the Earth the poles cannot get the direct rays from the Sun. But, the Equator can because it is always pointing towards the Sun, thus, getting more solar energy.
Hope this helped.

You not be doing this in a quiz. if you actually studied your work you would know the answer. the answer though is that they would use gdp per capita because it measures a smaller portion (person). this could show individual growth per person in the country.