Answer:
1 / i + 1 / o = 1 / f thin lens equation
(i + o) / o i = 1 / f
f = o i / (i + o) = 6 * -.4 / (-.4 + 6) = -2.4 / 5.6 = -.42 m
The focal length is -.42 m indicating a convex mirror
M = -I / O = -.4 / 6 = -.067 negative magnification indicates erect image
O = M * 1.1 = -.067 * 1.1 = -.073 m height of image
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