The correct answer is b.
The child is reaching for a toy which is not visible to him (hidden under a cloth), therefore, the child has a mental representation of the object in his/her mind. This action means that the child acknowledges that the objects continue to exist even when he/she can not hear or see them. This thought process is called object permanence and it is an ability acquired between the 4th and 7th month of a child's development.
Popliteus muscle
from: https://en.m.wikipedia.org/wiki/Popliteus_muscle
Escherichia coli (E. coli) bacteria normally live in the intestines of people and animals. Most E. coli are harmless and actually are an important part of a healthy human intestinal tract.
Answer:
Increased pollution I think is the right answer
Answer:
TYPE OF LIQUID SUBSTANCE RECEIVED
Explanation:
The independent variable in an experiment is the variable that the experimenter deliberately changes or manipulates in order to bring about a response in the dependent variable/measured variable.
In this experiment, the TYPE OF LIQUID was changed for each group of plant in order to see how it affects how the plants grew. Hence, the TYPE OF LIQUID is the independent variable while the dependent variable is the plant growth, which is dependent on the independent variable.