Which of the following scenarios would produce the Doppler Effect? Check all that apply.

A moving sound source (such as an airplane passing overhead)

A moving observer of a source (such as a person running past a loud
stereo)

A moving source and moving observer (such as kids chasing an ice
cream truck that is playing music)

A non-moving source and non-moving observer (such as person
watching television on a couch)

Hello I hope your doing great but I'm not understanding what your asking??

Explanation:

answer: the blood-brain barrier is a layer of specialized membranes and cell processes designed to keep undesirable substances from passing from the bloodstream into the precious tissues of the brain. while the blood-brain barrier does keep most bad things out of the central nervous system, it is not impermeable.

explanation:

there are 35 white marbles

step-by-step explanation:

y- yellow marbles

4y + 5 = 45

subtract 5 from both sides

4y = 40

divide for from both sides

y = 10

plug in 10 to get 40 yellow marbles then subtract by 5 to get 35 marbles

thus there are only 10 yellow marbles