The answer is A, friction.
Friction is the force that resists movement, and that's why oil is used as a lubricant and why ball bearings are used for machines that need to move with very little friction(i.e. bike wheels, roller skates, fidget spinners)
Answer B is too vague
C will probably reduce efficiency greatly, but not specifically in a way that turns work into thermal energy.
D is the same as C, except that it places the blame on the person using the machine, not the machine itself.
Hope I helped clear it up for you :)
<span>This is the "Follicle stimulating hormone (FSH)." This FSH hormone is essential to the reproductive system in general.
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First one, disease causing microorganisms
Involuntary as the muscle is a reflex
Answer:
Microvilli is very common in these cells. They increase the absorption area.
Explanation:
Epithelial cell surfaces show different structure shapes that allow the cells to adapt to and accomplish their functions. Most of these structures are related to the absorption surface and the need to move substances.
The development of microvilli is very common in epithelial cells. These are folds or finger-like projections emerging from the apical surface of the cell. <u>Their principal function is to absorb</u>. The microvilli of the intestinal epithelium are very uniform in size and distribution.
