In the south. Planet B takes only one year to orbit the star. The planets nearest the Sun contain only small amounts of substances that condense at low temperatures. All of the above. Light is a stream of energy particles, called photons.
Light is a wave of electromagnetic energy.
Neither a nor b. The light from a source moving away from us is shifted to longer wavelengths, causing a redshift. The light from a source moving away from us is shifted to shorter wavelengths, causing a blueshift. The light from a source moving away from us is shifted to longer wavelengths, causing a blueshift. The light from a source moving toward us is shifted to longer wavelengths, causing a redshift.