Each helium atom has two protons. Sketch models of helium-3 and helium-4 which have approximate masses of 3 amu and 4 amu, respectively. Label and differentiate protons, neutrons, and electrons in your models.

According to the tide table below what time of day will the highest tide occur? (2 pt) the highest tide will occur at

Before it was launched, a helium-filled balloon had a pressure of 201 kpa at a temperature of 27°c. at an altitude of 15,000 m, the pressure had decreased to 2.5 kpa and the temperature had dropped to -14 °c. the volume of the balloon increased to 59.3 m3. what is the original volume of the balloon? 13 m3 0.85 m3 0.077 m3 1.17 m3

Reactions in cells take place at about a. 40°c b. 0° c. 100°c d. 60°c