What is the best way to keep an ice cube from melting experiment?

During an experiment, readings for blood pressure in a persons body were found to be constant . however , when he measured by a different blood pressure cuff , the readings differed by 15 points for each reading. this difference indicates that the results are

Which of the following was not a major animal on land during the carboniferous period? amphibians insects both a and b none of the above

What organs comprise the respiratory system of a bird