However, the problem of deflection settings 'aim-off' required knowing the rate of change in the target's position. Both France and UK introduced tachymetric devices to track targets and produce vertical and horizontal deflection angles. The French Brocq system was electrical, the operator entered the target range and had displays at guns; it was used with their 75 mm. The British Wilson-Dalby gun director used a pair of trackers and mechanical tachymetry; the operator entered the fuse length, and deflection angles were read from the instruments.
What did the tachymetric devices do?
track targets and produce vertical and horizontal deflection angles

Gamal Abdel Nasser Hussein (Arabic: , IPA: [ml bdennse esen]; 15 January 1918 28 September 1970) was the second President of Egypt, serving from 1956 until his death. Nasser led the 1952 overthrow of the monarchy and introduced far-reaching land reforms the following year. Following a 1954 attempt on his life by a Muslim Brotherhood member acting on his own, he cracked down on the organization, put President Muhammad Naguib under house arrest, and assumed executive office, officially becoming president in June 1956.
What type of government did Nasser overthrow?
monarchy

YouTube is a global video-sharing website headquartered in San Bruno, California, United States. The service was created by three former PayPal employees in February 2005. In November 2006, it was bought by Google for US$1.65 billion. YouTube now operates as one of Google's subsidiaries. The site allows users to upload, view, rate, share, and comment on videos, and it makes use of WebM, H.264/MPEG-4 AVC, and Adobe Flash Video technology to display a wide variety of user-generated and corporate media video. Available content includes video clips, TV clips, music videos, movie trailers, and other content such as video blogging, short original videos, and educational videos.
How much did Google pay for Youtube in 2006?
US$1.65 billion