What geologic process could have formed the channel on Mars?

How many trophic levels are there in the following food chain? phytoplankton - shrimp - perch - pike - osprey

The probability of producing a normal child by two parents who are carriers for an autosomal recessive disorder is

How did the discovery of the rhesus factor affect society? o more patients died from having a transfusion with the wrong rhesus factor 0 new treatments during pregnancy could prevent harm to the developing child. o less donated blood could be used in the treatment of patients. the number of blood types was reduced by half