The gallbladder is a small pouch that sits just under the liver. The gallbladder stores bile produced by the liver. After meals, the gallbladder is empty and flat, like a deflated balloon.efore a meal, the gallbladder may be full of bile and about the size of a small pear. In response to signals, the gallbladder squeezes stored bile into the small intestine through a series of tubes called ducts. Bile helps digest fats, but the gallbladder itself is not essential.
U-substitution is for functions that can be written as the product of another function and its derivative. $$\int u du$$. Integration by parts is for functions that can be written as the product of another function and a third function's derivative.
Anything that is 120V and has electronic circuitry should be used only with a step-down transformer. Use it with a solid state voltage converter and you will fry it. The plug adapter in Neo11's link is all you will need if your device is 100-240V, but not if it is 120V only - for that you will need a transformer.