A log is added to a camp fire and is burned. This is an example of a _ change. Physical change or chemical ? Plz help thx

Can someone me with this and tell me what’s fracking and what does it have to do with carbon, carbon dioxide, or fossil fuels?

Four different thermometers were used to measure the temperature of a sample of pure boiling water. the measurements are recorded in the table below. thermometer temperature reading 1 temperature reading 2 temperature reading 3 w 100.1°c 99.9°c 96.9°c x 100.4°c 102.3°c 101.4°c y 90.0°c 95.2°c 98.6°c z 90.8°c 90.6°c 90.7°c the actual boiling point of pure water is 100.0°c. what can be concluded from the data about the reliability and validity of the thermometers?

Spirochetes have a twisting and flexing locomotion due to appendages called