Answer:
a) 
b)
Explanation:
Let´s use Doppler effect, in order to calculate the observed frequency by the byciclist. The Doppler effect equation for a general case is given by:
where:
Now let's consider the next cases:
The data provided by the problem is:
The problem don't give us aditional information about the medium, so let's assume the medium is the air, so the speed of sound in air is:
Now, in the first case the observer alone is in motion towards to the source, hence:
Finally, in the second case the observer alone is in motion away from the source, so:
Answer:
165.529454
Explanation:
According to the Pythagorean Theorem for calculating the lengths of a right angle triangle's sides, a^2 + b+2 = c^2, where c is the longest side (and the side opposing the right angle). So in your case it would be 150*150 + 70*70 = 27400. And √ 27400 is your answer.
Answer:
10. 3
11. 1
12. 3
Explanation:
10. Everybody has different things that they find stressful. Stressful situations are associated heightened anxiety, fear, and worry. Different situations and life events can trigger stress. Public speaking is a good example of a stressful situation, as it often makes people nervous and uncomfortable. The other options are not usually associated with stress
11. After division of a cell containing 46 chromosomes (diploid), the genetic content is divided equally between 2 cells, producing two daughter cells with 23 chromosomes (haploid). Sex cells are the only cells in the body that are haploid. At fertilisation, 2 haploid cells come together to form a diploid cell.
12. After the whales died, the bones settled in the ocean sediments that moved with the changing land. The bones would not be preserved after animal activity or floating in the ocean. Options 4 and 5 do not explain how the whale bones ended up out of the water.
To make sure there is no metal stuck in the wheat that could harm people
