Given: triangle BAC is similar to triangle DEF
a) Find FE (FE = 4.5?)
b) Find angle D

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).

This figure consists of a rectangle and semicircle. what is the perimeter of this figure use 3.14 for pi 60.84m 72.84m 79.68m 98.52m

Acompany that manufactures and sells guitars made changes in their product range. from the start they had 20 models. then they reduced the number of models to 15. as a result, the company enjoyed a 10% increase in turnover. - how much did the stock level change? in (%)