Huygens' principle (first described by the Dutch scientist Christiaan Huygens in 1678) uses geometry to determine the shape of a wavefront at a time t, given some initial wavefront at an earlier time. This can be constructed by imagining that the initial wavefront is a source of wavelets that propagate from each point at the speed of light. From this principle, one can determine the angles of reflection and refraction by considering the speed of light at each point on the wavefront. In this problem, we will explore some of these concepts.

The extermination of an entire targeted population is called genocide

Read the sentence below, then answer the question that follows. penny learned tolerance after rahj explained the traditions of his family and their practice of indian traditions. the underlined word in the sentence above can best be defined as a. a fair and understanding view of those whose culture, race, or nationality differs from one’s own b. an understanding of a set of organized beliefs and practices that are often centered around one or more deities c. the linking of a group of people based on common characteristics such as culture, beliefs, or common history d. a classification based on inherited physical or biological traits

What would a student most likely use if he or she wanted to consult a secondary source