The meniscus of mercury in a glass capillary tube is convex because of the very high density of mercury as compared with water the low surface tension of mercury the greater attraction of mercury atoms to the glass than to each other the weaker attraction of mercury atoms to the glass than to each other electrostatic repulsion between the glass and the mercury

The meniscus of mercury in a glass capillary tube is convex because of its high cohesion property where mercury stick together rather than spread to the tube compared to the water. The cohesive force is mutually attractive to each other, resulting to electrostatic repulsion to the tube.  Moreover, Mercury creates a solid-like state due to surface tension and low adhesion to the tube. 

answer: the exterior temperature of commercial jet planes as they leave the stratosphere and return to the ground increases steadily.

explanation:

the lower most layer of atmosphere is troposphere which extends from 0 to 12 km above the surface of the earth. the temperature initially decreases as distance is increased from the earth's surface. commercial jets fly in lower part of the stratosphere. the stratosphere extends upto 50 km. the temperature in stratosphere starts rising again due to presence of ozone which traps the uv rays.

thus, when the planes leave the stratosphere and return to the ground, the exterior temperature increases steadily.