As an engineer, your job is to build things that solve problems. When you first join the company, you're assigned small tasks and you solve them. As you grow professionally, the domain of these tasks becomes larger. It is a mistake to constrain the increase in domain to larger or more frequent diffs. Code is a tool you have for solving problems. If you were gardening, you might plant flowers or pull weeds. Increasing your scope does not mean planting more flowers or pulling more weeds (though you should expect to be faster and more proficient at that as you become more experienced). What it really means is looking up from the ground at the garden in its entirety, considering how your section fits in, and eventually helping to decide the whole garden's plan.
Washing hair removes excess sweat and oil, as well as unwanted products from the hair and scalp. Often hair is washed as part of a shower or bathing with shampoo, a specialized surfactant. Shampoos work by applying water and shampoo to the hair. The shampoo breaks the surface tension of the water, allowing the hair to become soaked. This is known as the wetting action. The wetting action is caused by the head of the shampoo molecule attracting the water to the hair shaft. Conversely, the tail of the shampoo molecule is attracted to the grease, dirt and oil on the hair shaft. The physical action of shampooing makes the grease and dirt become an emulsion that is then rinsed away with the water.
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