Answer:
Observers ahead of the wave observe an apparent increase in wave frequency
Explanation:
This is the Doppler Effect. The frequency of a wave increases when the source approaches the observer and decreases as the source recedes.
B, C, and D are wrong. Observers behind the source notice a decrease in frequency.
The moon pull back the waves so the sun can push them in the morning
Carbohydrate digestion begins in the mouth with the secretion of saliva but most occurs in the duodenum as a result of the secretion of
secretin.
They are called heterotrophs
Organisms that DO use the sun for energy are called autotrophs
Hint: Auto- Automatic- Autotroph (It automatically happens)
Hope this helps you :)