The octane rating of gasoline is a measure of the resistance to premature ignition, also known as engine knock. it is based on comparison to a mixture of 2,2,4-trimethylpentane, commonly known as isooctane (rating = 100), and heptane (rating = 0). an octane rating of 90 would compare to a mixture that is 90% isooctane and 10% heptane. isooctane is a highly branched alkane with the condensed structure (ch3)3cch2ch(ch3)2. draw the complete struckture and skeletal struckture.

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?

The excretory system, need answers for all: )

What is the atomic number of an atom that has 6 protons