Only 1- the experiment can not show a cause and effect relationship if there are more than one factors contributing to the outcome.
The answer top the question given above is letter c. Surface currents.
There are two types of ocean currents, surface current and deep currents.
Surface currents which are caused by winds,move warm water
away from the equator and cool water away from the poles. Deep currents on the other hand are driven by differences in water density.
The correct answer is by facilitated diffusion.
The procedure of continuous passive transport of ions or molecules through a semi-permeable membrane with the help of particular transmembrane integral proteins is known as facilitated or passive-mediated transport or facilitated diffusion.
It is a modification of osmosis incorporating a proteinaceous channel via which an extracellular solute can enter a cell in the absence of energy.
An example of force that acts at distance is gravity and an example of contact force is pushing a chair across the room
I think its false because gas exchange can happen in blood also
