A student conducts an experiment to determine the properties of an unknown thin spherical lens by measuring the image distance \(d_i\) for various object distances \(d_o\). The student plots \(\dfrac{1}{d_i}\) as a function of \(\dfrac{1}{d_o}\), producing the best-fit line shown in the graph. Which of the following claims correctly identifies the type of lens, its focal length, and the nature of the image formed when an object is placed at \(d_o = 0.20\text{ m}\)?