Final answer:
The eccentricity of an ellipse with a distance between the foci of 1.0 and the length of the major axis of 5.0 is 0.4.
Step-by-step explanation:
The question pertains to the eccentricity of an ellipse, which is a measure of its deviation from circularity. To find the eccentricity (e) of an ellipse, you can use the formula e = f / a, where f is the distance between the foci and a is the semi-major axis, which is half of the length of the major axis. Given that the distance between the foci is 1.0 and the length of the major axis is 5.0, first we calculate the semi-major axis as 5.0 / 2 = 2.5. Therefore, the eccentricity is calculated as e = 1.0 / 2.5 = 0.4.