Solve this
21,20,40,
a. 38
b. 76
c. 74
d. 78
e. 70

The decibel level of sound is 50 db greater on a busy street than in a quiet room where the intensity of sound is watt/m2. the level of sound in the quiet room is db, and the intensity of sound in the busy street is watt/m2. use the formula , where is the sound level in decibels, i is the intensity of sound, and is the smallest sound intensity that can be heard by the human ear (roughly equal to watts/m2).

Need on this geometry question. explain how you did it.

Drag the tiles to the correct boxes to complete the pairs. not all tiles will be used. match each division expression with the correct quotient.