An astronomical telescope longer than about 50cm is not easy to hold by hand. Estimate the maximum angular magnification achievable for a telescope...

An astronomical telescope longer than about 50 cm is not easy to hold by hand. Estimate the maximum angular magnification achievable for a telescope designed to be handheld. Assume its eyepiece lens, if used as a magnifying glass, provides a magnification of 3 × for a relaxed eye with near point 23 cm . Follow the sign conventions.

Express your answer using one significant figure.