How do we know ocean extremophiles found on hydrothermal vents are the U. C.A?

Sally and sue were investigating the topic of friction in science. they used a small car and a ramp as seen in the picture to test what they were learning. they knew that they slipped easily on waxed floors but not on carpet, so they decided to change the material on the surface of the ramp to see what happened. they planned to use glass, carpet, aluminum foil, and sandpaper and run the car down the ramp over each surface. what would be the best research question to guide the girls' experiment? a) does the amount of surface area affect the friction on the moving car? b) will the car travel fastest on the glass surface? c) how does the angle of the ramp affect the speed of the car? d)do rougher surfaces tend to create more friction than smooth surfaces?

Ayoung boy has been found and police are trying to locate his family they take a dna sample from him and begin collec dna samples from families who have missing children if police use dna samples only from the fathers, which type of dn technology can they use to identify the boy's parent? y-chromosome analysis omtdna (mitochondrial dna) analysis vntrs (variable tandem repeats) o pcr (polymerase chain reaction) analysis

Which is a kingdom? protistachordataprokarya mammalia