*Question*
The more efficient a device is, the greater the percentage of usable energy it produces. Theresa made a device that uses 25% of usable energy. Ryan made a device that uses 10% of usable energy. Theresa or Ryan made a device that is more efficient?
**Answer**
Theresa

*Question*
The higher the temperature, the more energy the particles have and the faster they will move and diffuse. Tina goes to the hot sauna. Her temperature increases, so the particles in her body will move slower or faster?
**Answer**
faster

*Question*
To reduce friction, oil is added to the engine. Dana wants things to slide around easily without too much friction, so she uses oil in amounts that are greater or smaller?
**Answer**
greater

*Question*
The greater the mass of the objects, the stronger the gravitational pull between them. Two small planets are near each other, and two large planets are near each other. The smaller planets, compared to the larger planets will have a gravitational pull that is weaker or stronger?
**Answer**
weaker