Which choice best explains the definition of a variable? 1.A variable is one way that scientists collect and record data in a scientific investigation.

2.A variable is something that can change and may affect the outcome in a scientific investigation.

3.A variable is a type of testable question that scientists ask when beginning a scientific investigation.

4.A variable is an educated guess that scientists make before conducting a scientific investigation.

Which best describes how fluids change as they travel through different portions of the convection currents? they change to solids at the outer portion of the convection currents. they change to solids at the inner portion of the convection currents. they become more dense at the outer portion of the convection currents. they become more dense at the inner portion of the convection currents

An ascending elevator, hanging from a cable, is coming to a stop. part a part complete identify all forces acting on the elevator from the list below. select all that apply. select all that apply. kinetic friction normal force tension weight static friction submitprevious answers correct part b draw a free-body diagram of the object. draw the vectors starting at the black dot. the location and orientation of the vectors will be graded. the exact length of your vectors will not be graded but the relative length of one to the other will be graded.

Mixing salt in water is an example of physical change