An other way of harvesting fusion energy is by using solar panels to capture the rays of the sun. The solar constant is 1361 W/m (if we round to a whole num- ber). However that value applies to space. On Earth the intensity of sunlight is only 200W/m on average if we account for day-night effects, clouds, time- of-day and latitudinal effects (oblique sun rays). For the next questions, let's assume that commercial solar panels have a 20% efficiency (i.e. they convert only 20% of the available sunlight into electricity). Question 5 [5 points]: Calculate how many square meters (or if you like: square kilometers) of solar panels are needed on Earth's surface to meet the world's energy demand of 12 x 102 Watts. Question 6 [5 points]: Put things in perspective, answer these: 1. Figure out what fraction of the land surface of the USA would be needed to (theoretically) power the world. 2. To power the entire world, would it be wise to situate most of these panels in Arizona? (why/why not)