Growth of pollen tube can be measured in terms of $:-$

When growth is exemplified by a root elongation at a constant rate,mathematically,it is expressed as:

Which one of the following has the least influence on cell elongation in a meristem?

Explain the phases of growth in plants.

Given below are two statements about plant growth.
Statement $I$: Curve for arithmetic growth is linear.
Statement $II$: Curve for geometric growth is exponential.
In the light of the above two statements,choose the most appropriate answer from the options given below.

In which of the following organisms does growth occur throughout their lifespan?