Nuri joins a game for a car. the rule is that nuri pick one key from box either a, b, or c. a box has two keys but only one can be used. b box has three keys but only one can be used. c box has two keys but none of them can be used. what is the probability that nuri can win the car ?

Look at the figure below: triangle abc is a right triangle with angle abc equal to 90 degrees. the length of ac is 5 units and the length of ab is 4 units. d is a point above c. triangle adc is a right triangle with angle dac equal to 90 degrees and dc parallel to ab. what is the length, in units, of segment cd?