Why do leap years repeat every four years?

Rock concerts musical instruments cell phones and contact lenses are just a few things that are possible because of

Why were so many distinctive cultures able to develop over time in asia?

Kate is 14 years old and just started taking dance classes with her friends at a local dance studio. this is her first time in a dance program, so everything is new to her. her friends convinced her to join the class since they have been enjoying it for a few months. how could the following terms her succeed in the dance class? ● secondary reinforcement ● identity vs. role confusion ● observational learning how could the following terms hinder her success in the class? ● circadian rhythm ● basal ganglia ● vestibular sense