Consider the relations, containing information on names of authors, and who is authoring which papers, respectively: Authors(auID, name)and Authoring(articleID, authorID), the answer can be expressed in either SQL or algebra.
1. List the articles authored by John Smith
2. List the co-authors of John Smith (authors who co-authored an article with John Smith)
3. List the authors that have written no paper with John Smith
4. List the authors who have all their papers co-authored with John Smith
5. List the papers authored by only one author
6. which author co-authored at least 1 paper with every author (without aggregate functions)
7. List pairs (authorID and Name) of authors who have written at least one common paper

Which of the following characters is acceptable to use in a filename? ? / – %

3.12: the speed of sound the speed of sound depends on the material the sound is passing through. below is the approximate speed of sound (in feet per second) for air, water and steel: air: 1,100 feet per second water: 4,900 feet per second steel: 16,400 feet per second write a program class the speed of sound that asks the user to enter “air”, “water”, or “steel”, and the distance that a sound wave will travel in the medium. the program should then display the amount of time it will take. you can calculate the amount of time it takes sound to travel in air with the following formula: time = distance/1,100 you can calculate the amount of time it takes sound to travel in water with the following formula: time = distance/4,900 you can calculate the amount of time it takes sound to travel in steel with the following formula: time = distance/16,400

Which resource produces the cleanest energy? -coal -gasoline -oil -wind