Amarine biologist is studying dolphin calls and notices that sometimes the calls sound louder based on the background noise in the water. what wave property of the dolphin's call is changing because of the background noise?
1.amplitude
2.frequency
3.speed
4.wavelength

Option C, Speed

Explanation:

Sounds travel faster in water. Their speed in water is five times of their speed in air.  

With such high speed, sound waves instead of going through ossicles bones (in the inner ears) directly vibrate the heavy bone behind the ears. Due to this reason, a person below water hears sound waves of higher frequency.  

However, while travelling through air sound waves reaches at lower frequency

Hence, option C is correct

"1. it should be, it has been for about 20 years, and it's really not much different in the end than breeding animals to have particular traits. there are always concerns about genetically engineered animals/plants affecting the environment in unexpected negative ways, but i can't think of an example where the fears didn't turn out to be baseless.  

first, as you point out, it would be a great advance in pharmacology, to be able to tailor drugs and their doses to me. the pros involve better medical treatment. the cons involve privacy issues like insurance companies denying coverage to people with genetic risk factors. looking at dna markers wouldn't affect the frequency of genetic diseases, but it would allow detection of them earlier. and ok, actually i suppose that if people used this information to avoid having children with genetic diseases, some might decrease in frequency."

light dependent reactions:

light independent reactions:

hope this !