Which of the following materials would be the least efficient in soundproofing a room: clay tile, plaster, or perforated acoustic ceiling material? be sure to use your knowledge of the coefficient of absorption in your explanation.

Impressions of tropical swamp plants were observed on rocks in polar regions. the impressions were dark black imprints, which means the fossils are examples of ( 1 ) the fossils tell us that polar regions ( 2 ) ( 1 ) a. carbonization b. mineralization c. trace fossils ( 2 ) a. had tropical plants that can grow in ice b. might have had a diffierent climate in the past c. will have abundent vegitation

Choose the factors that influence the climate of the u.s. northeast. distance from the equator proximity to large urban areas elevation secluded area distance from a large body of water

Which characteristics of temperature and salinity have the greatest influence on the movement of deep-ocean currentsa. warm and low salinityb. cold and high salinityc. cold and low salinityd. warm and high salinity