Carbon 14 has a half life of 5730 if a sample contained 70mg originally how much is left after 17190 years

Ababy stroller is a rest on top of a hill which is 10 m high. the stroller and baby have a mass of 20 kg. what is the potential energy of the baby and stroller?

5g of ammonium nitrate was dissolved in 60g of water in an insulated container. the temperature at the start of the reaction was 23.0°c and at the end it was 19.0°c. calculate the energy absorbed by the reaction.

Which sound characteristic is not affected by the relative motion of an object