Answer:
x(x)=1/4(30+60+x)
Step-by-step explanation:
minutes spent on math homework= x
minutes spent on history homework= 30 min
minutes spent on English homework= 60 min
Total minutes spent on homework = x+30 +60
Also
x= 1/4(x+30 +60)
x= x/4 + 90/4
x-x/4= 90/4
(4x-x)/4=90/4
3x=90
x=30
Hence time spent on maths=30 min
total time spent= 30+60+30
= 120 min
1/4 of 120 min= 30 mins!
Answer:
x=-3+3/5 brainliest plz
Step-by-step explanation:
7- B
8- C
I’m pretty sure please don’t hurt me if I’m wrong
Given: Sound Intensity ( I ) = 
We know, the approximate threshold of human hearing is at 1kHz. In watts/m^2 it's value is
⁻¹² W/m².
So, we can say, Reference sound intensity
= 10⁻¹² W/m².
We have formula for "sound intensity level LI in dB" when entering sound intensity.
LI = 10×log (I / Io) in dB
Plugging values of I and Io in formula.
LI = 10 × log (
)
LI = 10 × log (99000000)
= 10 × 7.99564
LI = 79.96 dB.
Therefore, 79.96 dB is the sound level for a noise that has an intensity of 9.9 × 10-5 watts/m2.
Answer:
blue is sus
Step-by-step explanation:
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