permite diferenciar los sonidos como agudos y graves ondas de radio, television, rayos x
diferencia 2 sonidos de igual frecuencia e intensidad
si se sujeta un resorte a un punto fijo y lo vamos soltando
si agitamos una cuerda y vibra hacia arriba y abajo
permite diferenciar los sonidos como fuertes o debiles
las ondas sismicas que producen los terremotos

respoder con:1)ondas longitudinales 2)timbre 3) ondas electromagneticas 4)ondas mecanicas 5)tono 6)ondas transversales 7)intensidas

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:

some of your causes might be acidic rain or natural wildfires that cause the parks to be degraded

hope this any more questions i am here plz mark brainliest

estuaries are the partially enclosed coastal bodies of brackish water formed at the mouth of sea where river meets an ocean. it is a transition zone between river and sea water so estuaries are influenced to both marine environment such as tides, waves and to riverine such as flow of fresh water and sediments. the mixing of sea and fresh water provide high level of nutrients, making estuaries a high product habitats.

many estuaries suffers degradation from a variety of human activities like erosion from deforestation, overgrazing, overfishing, drainage and eutrophication.

so from the above statement answers will be

1. false as estuaries are formed due to both brackish and freshwater.

2.true, due to high productivity estuaries are breeding ground for many marine species.

3. direct and indirect activities of man that contribute to pollution and deposition of sediments.