Question

below in two different ways.

Explanation:

Step1: Identify the line type

The figure is a line with points U and B, extending infinitely in both directions (since it has arrows on both ends), so it's a line. The symbol for a line is $\overleftrightarrow{}$.

Step2: Name the line using points

A line can be named by any two points on it. So we can name it using points U and B. One way is $\overleftrightarrow{UB}$ and another is $\overleftrightarrow{BU}$ (since the order of points on a line doesn't matter).

Answer:

Symbol: $\overleftrightarrow{}$
$\overleftrightarrow{UB}$ and $\overleftrightarrow{BU}$