A roller coaster with a potential energy of 235,200 J sits at the top of a 30 m high hill. What is the mass of the roller coaster? (Formula: PE = mgh) 800 kg
7,840 kg
8,000 kg
78,400 kg

2. when a government has total control over its citizens, including the media, it is a of government question 2 options: constitutional monarchy parliamentary democracy autocracy presidential democracy

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?

When deciding on an apartment what should you do first?