The answer must be 
since the triangular pyramid has 4 faces and each has an area of 30 
we should multiply that by 4 , so :
1 answer:
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Combine like terms (5y and -y= 4y) and the simplest form would be 4y+7
<h2>Answer:</h2><h2>The frequency of the guitar string vibrates back and forth 88 times in 1 minute = 1.5 Hz</h2>
Step-by-step explanation:
A hertz is used to measure one cycle (complete wave) of a vibration.
The number of cycles per second is the frequency, measured in hertz.
A guitar string vibrates back and forth 88 times in 1 minute
The vibrations in 1 second = = 1.466 Hz ≈1.5 Hz
The frequency of the guitar string vibrates back and forth 88 times in 1 minute = 1.5 Hz