The two dimensions an electrician must know when making a 90° stub bend are the_____________.

When making a 90° stub bend, understanding the desired rise and take up distance is crucial for achieving an accurate and efficient bend. The desired rise refers to how high you want the conduit to reach after the bend, which is essential for ensuring that the conduit meets specific installation requirements. The take up distance is the amount of length that the conduit will shorten due to the bend; knowing this allows the electrician to calculate how much conduit is needed before the bend is made.

Using both the desired rise and take up distance ensures that the electrician can create a bend that fits perfectly within the intended space, maintaining proper alignment and aesthetics. This combination directly impacts how the bend will position the conduit in relation to existing structures, such as walls or other conduits.

While other options mention dimensions related to conduit specifications, they do not capture the essential measurements that directly influence the execution of a precise 90° stub bend. Therefore, focusing on the relationship between the desired rise and take up distance provides the needed flexibility and accuracy in conduit installations.