Which scenario is an example of a closed system? You leave your hot cup of cocoa on the kitchen counter, and it eventually comes to room temperature.
You are cooking a pot of chili on the stove.
You put a cup of hot chocolate in the refrigerator, and it cools off.
You store a liquid in an airtight, uninsulated container.

An experimental procedure requires a 10 ml of acid to be dissolved

Plz mark brainliest 30 points 1) find the momentum of a 12 kg snowball that is rolling with a velocity of 9 m/s. 2) an 8 ball with a mass of .5 kg is sitting at rest. it is hit by the cue ball (1 kg) traveling at 2.5 m/s. if the cue ball is at rest after the collision, how fast is the 8 ball traveling after the collision? 3) two football players are running toward each other. if the offensive player is 75 kg and is running 8 m/s, how fast must the 60 kg defensive player run in order for the two players to hit and stop?

Which describes fat? a: a carbohydrate that produces energy b: a nucleic acid that directs cell function c: a lipid that stores energy d: a protein that speeds up a chemical reaction