be a sport: how many stumps are there in a cricket wicket?

Questions

- A plainsong chant sung by a chorus alternating with solo verse(s).?

- A silence in a performer's part indicated by symbols corresponding to certain beats.?

- In harmony this is a suspension which resolves upwards not downwards.?

(Fr.) - Held back.?

- A theme which is played backwards. This device was prominent in the Middle Ages in fugues and in 20th century serial music. Retrograde inversion describes a theme played backwards and upside-down.?