Which of the following elements will generally form only one covalent bond?

What is the symbol for the isotope with A = 31 and Z = 15?

5. Solve the linear differential equation x2 – xy = 4. Solve for y explicitly. Give the largest interval I over which the general solution is defined.  

4. Find an explicit solution of the initial-value problem

An _____________________ is an opera on a religious subject, such as an Old Testament story or the life of a saint.

As a moderately paced piece in triple meter, the _______________ makes an excellent contrast to the quick duple meter that was by far the most common in the opening and closing movements of Classical symphonies, quartets, and the like.

In classical _________________________ form entails the repetition of a clearly defined melodic unit, the theme, with various changes at each repetition.

The ___________________ is a form with popular leanings, dating back to the Baroque era, which begins with a full-fledged tune and returns to it after other episodes.

The principal genre of secular vocal music of the Baroque era was ______________, combining poetry, drama, music, vocal virtuosity, scenic splendor, dance, and more.

Which piano sonata by Beethoven is known as the “Moonlight” Sonata?