55:57 Which was not a result of the 1898 discovery of the four blood types and advances made during the two World Wars?
improved blood transfusion safety
effective blood preservation solutions developed
ability to separate different parts of blood for different uses
all blood types made compatible with each other

2. cheryl hears a new song on the radio every day during the week on her commute to work. surprisingly, when the song comes on at a party on saturday night, she knows most of the words without trying. describe the three ways that we use cognition to learn without reinforcement. which type of cognitive learning without reinforcement best explains how cheryl knew the song lyrics? explain your answer.