In the controlled experiment, a scientist is studying how long it takes parachutes of different sizes to fall to the ground. what are the manipulated/experimental variables?

The size of the parachutes.

Explanation: In this experiment we have two variables: The size of the parachute and the time that the parachute needs to cover a given distance (from a plane to the ground, for example)

The only thing that the scientist can modify, the independent variable, is the size of the parachute, and this will impact in the dependent variable, the time it needs to fall to the ground.

explanation:

earth's surface is mainly heated by the absorption of infrared radiation from the sun.

evaporation occurs because molecules in liquid water are warmed ( usually by the sun) and vibrate quicker, becoming less dense and rise.

condensation occurs because molecules in water vapor are cooled and therefore vibrate more slowly thus becoming more dense and eventually fall to earth.

lines of equal barometric pressure on a weather map are called: isobars : lines of equal temp on a weather map are called: isotherms.​

c.the charges if the proton and electron and gravity