Open the brackets using the correct verb form.



Different Spiral Types


The main feature of this exchanger type (to be)Ответ
that there is a single passage for each fluid. In actual operation, the cold fluid (to enter) Ответ
at the periphery and flows towards the center where it (to exist) Ответ
via the cover. The hot fluid (to go)Ответ
in the opposite direction, giving countercurrent flow. The single channel makes the unit well suited to handling fouling liquids with the original design being known as the Type I. Next unit (to use) Ответ
for final cooling of the treated sludge.