How do you calculate the net force if two or more forces act in the same direction

when you breathe in, or inhale, your diaphragm contracts (tightens) and moves downward. this increases the space in your chest cavity, into which your lungs expand. the intercostal muscles between your ribs also enlarge the chest cavity. they contract to pull your rib cage both upward and outward when you inhale.

what is shown in the image?

eukaryote

chloroplast

mitochondrion

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