Need help... A group of students are designing a field study to investigate the length of time a traffic light remains yellow. In the interests of safety, one of the students suggested the following rules:

• Study the traffic lights at intersections where the speed limit is 70 km/h or less.

• Avoid rush hour. Study traffic lights outside of times when people are going to and from work and school.

Indicate how each of these rules may limit the useful data that comes out of the investigation.

How does the amount of energy required to hold each proton and neutron in the nucleus compare to the energy released when they are removed?

Astudent is performing an experiment comparing sound and light waves. the student gathers the following data. what conclusion does the student most likely make based on this data? light waves always travel the same speed; however, the speed of sound is determined by the medium that it travels through. all sound waves always have the same energy, so the temperature of the medium does not affect wave speed. light needs to vibrate particles, so it travels fastest in tightly packed solids, while sound does not need a medium, so it travels fastest in a gas. tightly packed particles in solids slow down the light waves; however, sound waves make particles bounce into each other, so they travel faster in solids.

Oxygen and nutrients are moved through the body by the: a. circulatory system c. lymphatic system b. digestive system d. reproductive system