An object is held at a distance of 20cm from a concave lens of focal length 80cm. What is the position and size of the image if the object is 2cm high?

A. -16cm C. 18cm

B. 16cm D. -18cm​

Point charges q1=+2.00μc and q2=−2.00μc are placed at adjacent corners of a square for which the length of each side is 1.50 cm . point a is at the center of the square, and point b is at the empty corner closest to q2. take the electric potential to be zero at a distance far from both charges. part a what is the electric potential at point a due to q1 and q2? express your answer with the appropriate units.