An element is also a pure substance. The reason for this is because an element contains only one type of particle.
Option A is correct
Noble gases have a complete outer shell meaning they have eight valence electrons (octet rule); having eight electrons makes the atom very stable and unlikely to react because they don't need anymore electrons.
Answer:
d. the presence in the body of the virus that causes AIDS
1. Water is abioitic and is needed by every living organism Soil is abioitic and is needed by plants Trees and other plants release water vapor from their leaves (a process called transpiration) that create humidity (which in turn influences how much rain falls in an area) The climate in an area influences the special adaptations that plants and animals have. For example: warm fur coats and thick layers of fat to keep warm in cold climates, animals in dry, hot climates (desert) have large ears to release heat and cool down. Biotic factors also influence abiotic factors. Animals produce waste (go to the bathroom) which in turn will become nutrients in the soil.
2. decrease heat will affect biotic factors, like animals, warmth.
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