Jeff is a landscaping contractor and lifts a rock weighing 600 pounds by wedging a board under the rock. jeff weighs 150 pounds and puts all of his weight on the lever. how much mechanical advantage did the lever provide to jeff in lifting the rock?

Alidded glass container is filled with a colored gas. after a period of time, it is observed that the gas is uniformly spread throughout the box and that the movement has slowed considerably. next, a warm iron plate is carefully placed under the box. why is there resumed movement of the gas in the container?

What is the measured amount of a product obtained from a chemical reaction?

Show how to convert the temperature 84.7° c to kelvin. include all steps and label the final answer