Which of the following is one role of rna polymerase during transcription?
to switch uracil with thymine on the exposed gene
to build a molecule of mrna
to break down an already existing protein
to produce a start sequence

By water evaporation from the leaves is created a negative pressure at the top of the tree that promotes the ascension  of the water through channels that are called xylem. there are also two molecule forces that are involved: the intra-water molecules cohesion (water molecules stick to each other) and the adhesion when the water molecules stick to the channels they are running in. this is what enables water to go from the roots to the top of a tall tree.

Advection fog occurs when warm air blows over a cold surface like snow and since tropical water is warm advection fog rarely forms over it