In order for heat to flow there must be... * A. identical tempatures
B. a difference in tempatures
C. a difference in altitude
D. an electrical current present

Although respiratory organs vary across different organisms, they all contain respiratory surfaces that have a large surface area and are extremely thin. explain why having an extremely thin respiratory surface with a large surface area is advantageous for the process of gas exchange

Five different substances are given to you to be dissolved in water. which substances are most likely to undergo dissolution in water? check all that apply. view available hint(s) check all that apply. sodium fluoride, naf octane, c8h18 propanol, ch3ch2ch2oh potassium iodide, ki benzene, c6h6

Elizabeth has two separate samples of the same substance. sample is in the liquid state, and the other is in the solid state. the two samples most likely differ in which property?