I'm stuck on the same question, as well :(
Answer:
129.74 Hz
Explanation:
Given:
Wave velocity ( v ) = 346 m / sec
wavelength ( λ ) = 2.69 m
We have to calculate Frequency ( f ) :
We know:
v = λ / t [ f = 1 / t ]
v = λ f
= > f = v / λ
Putting values here we get:
= > f = 346 / 2.69 Hz
= > f = 34600 / 269 Hz
= > f = 129.74 Hz
Hence, frequency of sound is 129.74 Hz.
Answer:
Both are examples of negative feedback regulation.
Explanation:
The maintenance of the homeostasis in the body is controlled by the the feedback regulation of the body. Two main types of feedback regulation are positive regulation and negative regulation.
The negative regulation occurs when the final product of the reactions inhibits the further secretion of that product. In the given examples of aldosterone and calcium mechanism, the secretion of aldosterone and calcium decreases as the normal levels are acheived in the body.
Thus, the answer is both are examples of negative feedback regulation.
I think you meant to say "procedure" instead of "produced".
Choice B is the answer as it is the safest and most sensible (to prevent damage to clothing or start a fire for example). The other choices are nonsensical or silly.