Answer:
The magnetic field of Earth is caused by currents of electricity that flow in the molten core. These currents are hundreds of miles wide and flow at thousands of miles per hour as the earth rotates. The powerful magnetic field passes out through the core of the earth, passes through the crust and enters space.
You want the solution that's going to enter your bloodstream to have a similar solute composition (isotonic), otherwise you'll lower the concentration of the solute in your blood - in this case, salt.
Answer:
Independent variable
Explanation:
In a scientific experiment, an independent variable is that variable which the experimenter changes or manipulates in order to effect an outcome. Only one independent variable should be tested at a time in a good experiment, all other variables should be kept constant. The initial independent variable in this experiment is TYPE OF SUBSTANCE put in the students' eyes.
However, according to the question, the researcher did not keep track of what they did in that free time. Hence, many of the people receiving the medicine spent their time outside and many of the people receiving the placebo spent their time inside. The location of every student should be a CONSTANT VARIABLE i.e. same for all students but now it has become an INDEPENDENT VARIABLE because it has been changed.
Chordata
notochord is a mesodermally rod like structure which forms vertebral column in higher vertebrates