Two students are riding on a sled down a 100 m hill. It takes 25 seconds to 2 points reach the bottom of the hill. What is their speed?"
250 m/s
250 mph
4 m/s
0.25 m/s

Avariable that is not being directly tested during an experiment should be changed varied experimented controlled

Exit what is the density of an object having a mass of 5.0 g and a volume of 45.0 cm3?

Calculate the ph at the equivalence point for the titration of a solution containing 150.0 mg of ethylamine (c2h5nh2) with 0.1000 m hcl solution. the volume of the solution at the equivalence point is 250.0 ml. kb forethylamine is 4.7 × 10−4 .