Here is the distribution of blood types for randomly chosen black americans: blood type: O A B AB
probability: 0.49 0.27 0.20 0.04

joe can safely receive blood transformations from people with blood types O and B. what is the probability that a randomly chosen black american can donate blood to joe?

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?