Mr. and mrs. tew attended this summer band concert to her their son play his violin. when they sat down in their seats, they noticed that there were dead moments. that is, places in the music when they could not hear anything! they decided to move and sit directly in front of the band in the third row. how can you explain the dead spots they experienced?

a: some sound waves cancelled each other out.

b: sound waves reflected off of the ceiling and walls.

c: the sound waves underwent constructive interference.

d: some of the students stopped playing for a few seconds.

gold i'm pretty sure i might be wrong

ecological efficiency: % of usable energy transferred as

biomass from one trophic level to the next typical is 10% efficient (90% of

energy is lost),is diagramed as the pyramid of energy flow. then osprey eagle

are tertiary consumer and the shrimp are primary consumer, so to balance

mass of shrimp (1/0.1) / 0.1 = 100 kg 

you know that this symptom is misleading and quite often is related to: heart attack

a heart attack is a condition that occurs when the blood flow that transports oxygen to the heart muscle is damaged or cut off completely. the coronary arteries that supply the heart muscle with blood flow can be blocked by the accumulation of plaque. also, when the plaque within the heart artery breaks, it creates blood clot that can also hinder the blood flow. men that are over 45years of age and women that are over 55years of age are at risk of having a heart attack. the symptoms of a heart attack include chest discomfort, chest pain, coughing, and shortness of breath.