How can you describe your location? You might use a familiar system. You might say, 'I live at 1234 Main Street, Springfield, Ohio.' You could also say, 'I live right behind the Elementary School.' This method uses the school as a point of reference. Another example is, I am at the corner of Maple Street and Main Street. Both streets may be a good reference for anyone living in your town. Scientists must be able to pinpoint a feature they are studying. Scientists use a special system to describe locations. They use latitude and longitude as a reference. Lines of latitude and longitude form a grid. You may have used a grid system while doing graphing. This grid is centered on a reference point. Zero latitude is the equator. Lines of latitude run east to west. They divide the Earth from North to South. Lines of longitude run from north to south. They divide the Earth from East to West. Zero longitude runs through Greenwich, England. You may have heard the term, Greenwich Mean Time, or GMT. The system of latitude and longitude works well for objects that do not move.

Question: "Which way do lines of latitude run and what do they divide?"

Response: "Runs horizontal and the divide north and south"

A: no

Duane was hungry, but he hurried through the ample supper that was set before him, urged on by curiosity and astonishment. The only way he could account for his presence there in a ranger's camp was that MacNelly hoped to get useful information out of him. Still that would hardly have made this captain so eager. There was a mystery here, and Duane could scarcely wait for it to be solved. While eating he had bent keen eyes around him. After a first quiet scrutiny the rangers apparently paid no more attention to him. They were all veterans in service--Duane saw that--and rugged, powerful men of iron constitution. Despite the occasional joke and sally of the more youthful members, and a general conversation of camp-fire nature, Duane was not deceived about the fact that his advent had been an unusual and striking one, which had caused an undercurrent of conjecture and even consternation among them. These rangers were too well trained to appear openly curious about their captain's guest. If they had not deliberately attempted to be oblivious of his presence Duane would have concluded they thought him an ordinary visitor, somehow of use to MacNelly. As it was, Duane felt a suspense that must have been due to a hint of his identity.

Question: "In this scenario, Duane is seen doing what?"

Response: "Eating Supper"

A: yes

Physical properties include the state of matter. We know these states as solid, liquid, or gas. Properties can also include color and odor. For example, oxygen is a gas. It is a major part of the air we breathe. It is colorless and odorless. Chlorine is also a gas. In contrast to oxygen, chlorine is greenish in color. It has a strong, sharp odor. Have you ever smelled cleaning products used around your home? If so, you have probably smelled chlorine. Another place you might smell chlorine is at a public swimming pool. The chlorine is used to kill bacteria that may grow in the water. Other physical properties include hardness, freezing, and boiling points. Some substances have the ability to dissolve in other substances. Some substances cannot be dissolved. For example, salt easily dissolves in water. Oil does not dissolve in water.

Question: "What are the properties of Chlorine?"

Response: "it is a gas, greenish in color, has a strong sharp odor"

A:
yes