Which method is more useful in estimating the age of objects that are known to be several million years old? c-14 dating since carbon isotope has a shorter half-life than uranium uranium dating since uranium isotope has a longer half-life than carbon c-14 dating since carbon is present in both living and non-living objects uranium dating since uranium is present in both living and non-living objects

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?

Which must be kept in mind when determining if an explanation is correct? check all that apply.which must be kept in mind when determining if an explanation is correct? check all that apply.

What will happen to the amount of food available as a pondwater ecosystem ages