Answer:
B. 25 feet
Explanation:
In most cities in US, passenger car brakes must stop a car moving at 20 miles per hour at 25 feet.
Therefore, the correct option is "B" 25 feet
Answer:
False
Explanation:
It is better to be logical when proving a point
The following answers apply;
- Changes in magnetic properties of rock
- Decrease in well water levels
- Increases in radon gas in groundwater
- Foreshocks
These other choices may be good indicators of an imminent volcanic eruption;
Movement of magma
Increase in sulfur dioxide and carbon dioxide ground emissions
Answer:
The leverage or mechanical advantage of pulleys is less obvious, but you can "gang" multiple pulleys together into two sets (blocks) and run the ropes back and forth between the two sets to increase the number of lengths of rope running between them. One end of the rope is connected (fixed) to one of the blocks, and you get to pull on the other end after it is passed back and forth between the blocks of pulleys. This is sometimes called a block and tackle arrangement. With a hook on each side of the block set, you can move a heavy load much like levers do, by multiplying the force. You have to pull more rope just like you have to move a lever more on one side of the fulcrum as compared to the other. When you get all the rope pulled out that you can, you can not move the load anymore because you have become "two-blocked" which means the two blocks are together. Credits to: Moin Khan