10. where is methane produced?
a in the exhaust systems of automobiles
ob in the heating systems of homes and other buildings
c in the digestive systems of livestock and certain bacteria
d in the production systems of coal-burning power plants

Which of these is most likely to happen if parallax measurements of star distances are taken after a gap of six months? the results would be accurate the results would be inconsistent the results would not be valid the results would not be repeated

What substance is the most acidic. lemon juice. tomato juice. sodium hydroxide. water

Fill in the blank with the best word to complete the sentence. white blood cells protect against and aid in blood clotting when injuries are sustained.