Hello there!
For this:
1). Convert 10km to meters!
2). Convert the 30 minutes into seconds!
3). Use the following formula to solve for speed!
speed= distance/time
Note: The units should automatically work out to m/s. :)
My goal is to make sure you understand the problem, which is why I won't be giving you the answer. It'll be more work now, but less work in the future! :)
Hope this helped!
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Answer: d. I or II
Explanation: A traveling wave has speed that depends on characteristics of a medium. Characteristics like linear density (μ), which is defined as mass per length.
Tension or Force (
) is also related to the speed of a moving wave.
The relationship between tension and linear density and speed is ginve by the formula:

So, for the traveling waves generated on a string fixed at both ends described above, ways to increase wave speed would be:
1) Increase Tension and maintaining mass and length constant;
2) Longer string will decrease linear density, which will increase wave speed, due to their inversely proportional relationship;
Then, ways to increase the wave speed is
I. Using the same string but increasing tension
II. Using a longer string with the same μ and T.
Answer - true
Explanation-
Answer:
97% will sink below the water
Explanation:
Waters density is 1 g/cm3
If an object's density is greater than 1g/cm3, it will sink. If it's less then it would float. 1-0.97 = 0.03. Only 3% of the ice would show while 97 will be under.