Pl help A teacher looks at his students test to see which topics his students are still struggling with. What is this a Observational Study or Survey or Experiment?

'which of these statements about the scientific method is not true? all experiments must follow the same number of steps in the procedure. experiments may be repeated several times. some unexpected results can be beneficial. experimental results may or may not support the hypothesis.

In this experiment, the was intentionally manipulated. it is the independent variable. the dependent variables that were measured were the

Amniocentesis is a process in which amniotic fluid is taken from the mother's womb to identify any genetic abnormalities in the fetus. how would the discovery of the human genome contribute to this process?