Q: An electrician has to repair an electric fault on a pole of height 4 m. He needs to reach a point 1.3 m below the top of the pole to un dertake the repair work the length of ladder that he should use, which when inclined at an angle of 60° to the horizontal would enable him to reach the required positions is :

• A. $$ {9\sqrt{3}\over 10}{\ meter}$$
• B. $$ {3\sqrt{3}\over 10}{\ meter}$$
• C. $$ {3\sqrt{3}\over 5}{\ meter}$$
• D. $$ {9\sqrt{3}\over 5}{\ meter}$$