John is trying to figure out how substance passes through the cell membrane. He noticed two different cases, case A and case B. In case A active transport is involved, but in case B diffusion is involved. He needs to do further study to learn about the details of these processes.  In which case the substance moves down the concentration gradient, case A or case B?  Hint: Active transport occurs when a substance passes through the cell membrane with the help of extra energy. This happens when a substance moves from an area where it is less concentrated to an area where it is more concentrated. This is the opposite of diffusion. The substance moves up, instead of down, the concentration gradient. Like rolling a ball uphill, this requires an input of energy. The energy comes from the molecule named ATP (adenosine triphosphate). The energy allows special transport proteins called pumps to move substances to areas of higher concentration. An example is the sodium-potassium pump.
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Answer: case B


Andrew just moved into his new apartment but realized he made a mistake. He loaded a box too heavy for him to lift. He decides to try to push the mox into his house from the back of his building which has a very rough path and struggles to get the box in the house.  Will the amount of effort needed to push something across a rough surface increase or decrease as compared to a smooth surface?  Hint: All machines make work easier, but they don’t increase the amount of work that is done. You can never get more work out of a machine than you put into it. In fact, a machine always does less work on an object than the user does on the machine. That’s because a machine must use some of the work put into it to overcome friction. Friction is the force that opposes motion between any surfaces that are touching. All machines involve motion, so they all have friction. How much work is needed to overcome friction in a machine depends on the machine’s efficiency.
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Answer: increase


Hill town was full of gasoline powered vehicles, while Valley town 50 miles away, banned all gas powered vehicles and allows only electrical vehicles or horse-and-buggies.  Which town had fewer volatile hydrocarbons in the atmosphere?  Hint: Gasoline-powered vehicles emit a lot of harmful materials. Nitrogen oxides are formed when atmospheric nitrogen reacts with oxygen at the high temperatures found in a car engine. Carbon monoxide is a by-product of incomplete combustion of hydrocarbons. Evaporated and unused fuel releases volatile hydrocarbons into the atmosphere to help form smog. The presence of a catalytic converter in the exhaust system of the car causes these materials to react and be changed into less harmful products.
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Answer: