Answer:
70.07 Hz
Explanation:
Since the sound is moving away from the observer then
and
when moving towards observer
With
of 76 then taking speed in air as 343 m/s we have


Similarly, with
of 65 we have

Now

v_s=27.76 m/s
Substituting the above into any of the first two equations then we obtain

I believe that the loss of Phyllis' recollections is thought to be the most heartbreaking side effect of her ailment in light of the fact that once a man's memory scatters then piece of the individual begins to vanish with them. A memory holds a considerable measure of essential data, for example, people's identity, where They have lived, and their connections that they have had with individuals.
Because it can pollute the air and cause wild life to eat stuff that has been contimanted by the air
<span>procedure would most likely help determine a chemical property of the substance is : exposing it to a flame to see if it catches on fire
Chemical property is the characteristic that a substance has that differntiate it with another substance. The most common charatcteristics that most scientists wanted to know are :
- It's flamability
- It's radioactivity
- Its toxicity
By throwing the object into fire, we will easily find out these 3 characteristics</span>
Answer:
Archaeologist use radioactive isotopes to determine the ages of various objects, rocks and materials. This is called radioactive dating. Radioactive isotope Carbon-14 is widely used for this dating process.
Scientists use radioactive isotopes in agriculture to monitor or study the uptake and use of essential nutrients by plants from the soil. This helps to determine viability, productivity and nutritious ability of the plants on a piece of land.
Geologists use radioactive isotopes to trace leaks in underground water storage, pipes. Radioactive isotopes are effective tracers because their radioactivity can be easily detected.