3. (10 points) By what percent would the energy output of an underwater turbine increase if its blades are 2% longer and the speed of the water is 3% faster? 4. (20 points) The surface (photosphere) of the Sun is approximately 5,500C with a radius of about 700,000 km. (a) Compute the peak wavelength (in m) of the radiation that the Sun emits, and identify the associated type of radiation (e.g., ultraviolet, visible, or infrared). (b) Compute the power (in Watts) of the sunlight that would be received by a 1m solar panel that is receiving direct sunlight (i.e., pointed perpendicular to the Sun's rays) aboard a spacecraft near Earth's orbit (i.e., 149 million km from the Sun). Explain why your answer differs from the 340 W/m average incoming solar radiation received by Earth's surface