Which structures are listed in order from least complex to the most complex? a. cardiac cell , heart , mitochondria, circulatory system b. mitocondria, cardiac cell, heart , circulatory system c. mitochondrial, heart , cardiac cell, circulatory system d. circulatory system, heart, cardiac cell, mitochondria

1. you serve a volleyball with a mass of 2.1 kg. the ball leaves your hand with a speed of 30 m/s. the ball has energy. calculate it. 2. a baby carriage is sitting at the top of a hill that is 21 m high. the carriage with the baby weighs 12 n. the carriage has energy. calculate it. 3. a car is traveling with a velocity of 40 m/s and has a mass of 1120 kg. the car has . calculate it.