You are given a new situation: 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. and a 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. Please answer this question : Will decreasing the amount of friction make pushing an object more difficult or less difficult?
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Answer: less

You are given a new situation: David got five exercise tips from his personal trainer, tip A, tip B, tip C, tip D, and tip E. Tip A involves weight lifting, but tip B does not involve weight lifting. Tip C involves running, but tip D does not involve running. Finally, tip E does not involve any exercise at all. David has to find out which tips are most useful for him. and a hint : In exercises such as weight lifting, skeletal muscle contracts against a resisting force (see Figure below ). Using skeletal muscle in this way increases its size and strength. In exercises such as running, the cardiac muscle contracts faster and the heart pumps more blood. Using cardiac muscle in this way increases its strength and efficiency. Continued exercise is necessary to maintain bigger, stronger muscles. If you don't use a muscle, it will get smaller and weakerso use it or lose it. Please answer this question : In which tip the cardiac muscle would be more efficient, tip C or tip D?
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Answer: tip C

You are given a new situation: There are two cats sitting outside in the sun. One of them is white and one of them is black. Tina sees them and goes to pet them both. and a hint : Light may transfer its energy to matter rather than being reflected or transmitted by matter. This is called absorption . When light is absorbed, the added energy increases the temperature of matter. If you get into a car that has been sitting in the sun all day, the seats and other parts of the car's interior may be almost too hot to touch, especially if they are black or very dark in color. That's because dark colors absorb most of the sunlight that strikes them. Please answer this question : Will the white cat or the black cat be warmer?
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Answer:
black cat