The sound level, B. In decibels (dB), of a sound with an intensity of I is calculated in relation to the threshold of human hearing, I0, by this equation
B = 10log(i / i0)
The threshold of human hearing is 10^-12
watts/meter?
The sound level of a Jet plane is approximately 140 dB. The intensity of the sound of a Jet plane is approximately ?
watts/meter^2?

Lance lived in portugal and brazil for a total of 14 months to learn portuguese. he learned an average of 130 new words per month when he lived in portugal, and an average of 150 new words per month when he lived in brazil. in total he learned 1920 new words. write a system of equations to represent the situation. use x to represent portugal, and y to represent brazil