#### You are provided with a convex lens and a distant object. Using the parallax method, determine the focal length of the convex lens. The lens is placed in front of the object, and you observe the apparent shift when viewing the object through the lens from different angles. Given: • Distance between the object and the lens, Do = 50 cm • Apparent shift of the object, d = 2 cm • Distance between your eyes and the lens, De = 25 cm  Assumptions: • The lens is thin and the lens thickness is negligible. • The lens is properly aligned and centered.Option: 1 14.12 cmOption: 2 17.87 cmOption: 3 16.67 cmOption: 4 15.26 cm

Apply the parallax method formula to calculate the focal length (f) of the convex lens:
$f= \frac{D_{o}\times D_{_{e}}} {D_{o}+ D_{e}}$$f= \frac{50 cm\times 25 cm} {50 cm+ 25cm}$

Substitute the given values into the formula:
$f= \frac{50 cm\times 25 cm} {50 cm+ 25cm}$

$f= 16.67 cm$

The focal length of the convex lens, determined using the parallax method,
is approximately 16.67 cm.