How can you increase the solubility of most solids in water?

The only effective way to do that is to heat the water.

Others may come along and tell you to crush the solid into tiny pieces, or stir the water or shake the jar while the solid is dissolving.  Those actions can make the solid dissolve faster, but they don't change the amount of solid that eventually dissolves if you wait long enough.  The only way I can think of to do that is to make the water warmer.  

electromagnetic waves travel through space with vacuums. give me brainliest if right.

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.