Answer to Question 1 congregational hymn-singing, chanted prayer, modern gospel songs, musical chanting of sermon, invitational song, singing of the word Amen.
Answer to Question 2 Intonation refers to the extent to which the notes match the correct pitch. In the Western music-culture, precise intonation means making the pitches being performed match the standard pitches in cycles per second (c.p.s.) of the Euro-American chromatic scale1. For example, modern orchestras and other performing ensembles practicing within this music-culture, normally tune their instruments to the pitch of A above middle C, which is required to be exactly 440 cycles per second (c.p.s.). In order for this particular pitch to be in tune, the vibrating source of the instrument's soundwhether a moving string, column of air, stretched membrane (drum skin), or the instrument itself (e.g., the wood bars of a xylophone)--must be moving at a constant rate of 440 c.p.s. If the pitch frequency is either too fast or too slow, the pitch will sound out of tune. For the ensemble to sound in tune, every musician is required to play the same exact set of pitch frequencies. Intonation that is out of tune deviates from the pitch frequencies that are accepted as standard in the Western music-culture.
But it is important to keep in mind that the requirement to produce pitches that are in tune is arbitrary.
Thus, sliding in between the accepted standard pitches and bending the pitches of certain notes may be quite in keeping with the style of the music in question. In fact, music such as the blues is filled with blue notes, notes purposely produced above or below the standard pitches of Western culture. In blues music, this approach to pitch intonation significantly contributes in a very positive and emotional way to the unique style and sound of the genre. Leave out the blue notes and you don't have blues music
1 The Euro-American chromatic scale divides every octave into twelve pitches that are equally spaced apart (equal temperament). The musical interval or distance between any two successive pitches is always heard as exactly one half-step.