What is a main difference between a mixture and a pure substance? a A mixture looks the same throughout, but a pure substance does not. b A mixture can be made up of a single compound, but a pure substance cannot. c A mixture is only a liquid, but a pure substance can be in any state. d A mixture can vary in composition, but a pure substance has a set composition.

Wo audio speakers are placed on a vertical rail. speaker a is placed at head-level while speaker b is place at some variable height, \delta yδy, above speaker a. both speakers receive simultaneous input from a sine-wave generator so the speakers each produce a pure sinusoidal sound wave with a wavelength of 0.531 meters. calculate the lowest height that speaker b can be placed above speaker a to produce a minimum of sound heard by person standing \delta x = 7.86δx=7.86 meters directly in front of speaker a.

Since the investigative question has two variables, you need to focus on each one separately. thinking only about the first part of the question, mass, what might be a hypothesis that would illustrate the relationship between mass and kinetic energy? use the format of "if…then…because…” when writing your hypothesis.

Simple machines can a. increase force only b. decrease force only c. increase or decrease force