Ethan visited the Crosby Observatory at the Orlando Science Center. The observatory houses the largest refracting telescope available to the public in Florida. One night, he observed several stars that all seemed to be equally bright. However, one of the astronomers explained that each star actually had a different absolute brightness. What information do you need to calculate a star's absolute brightness? Choose the two that apply. Group of answer choices

How much would the freezing point of water decrease if 4 mol of sugar were added to 1 kg of water(k=1.86 c/mol/kg for water and i=1 for sugar

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?

How would the number of moles (n) of o2 change if the atmospheric pressure doubled but all other variables stayed the same