The death rates in the united states decreased more than 40 percent from 1930 to 2015. which factor could have contributed to this increase? a. increased food insecurity b. better medical facilities and treatments c. decreased farmland d. refusal of vaccines e. illiteracy

Fossils can only be formed when? if mud, silt or tar is in the area to preserve the fossil ierosion does not occur and allows the fossil to form oxygen and microorganisms cannot decay the bones the area is dry and does not contain mud or silt

Researchers want to use edna to look for an invasive species in the water which of the steps would be likely do last

Some birds look for food near cattle and other livestock. the movement of the cattle churns up the ground, making insects available to the birds. the cattle appear to be unaffected by the presence of the birds. what kind of relationship exists between the birds and the cattle? o a. parasitism o b. commensalism o c. predation o d. mutualism