what year did ancient rome rise and fall

Psychologists studying infant memory want to determine at what age babies can remember specific events. an experimenter uses several puppets to demonstrate a series of actions while the infant watches. after a delay, the experimenter records how many of the actions the child imitates when playing with the puppets. what is the dependent variable?

How would having more railroad tracks be advantageous during a war

How did the spanish prove to be excellent allies in the war? give examples?