Answer:

Explanation:
From the question we are told that:
Density 
Frequency
Length
Generally the equation for Frequency is mathematically given by

Therefore



Pass a validated official test ?
Should be 250m. check with your teacher and let me know
<span>Brass is an <u>alloy</u>. An alloy
is a mixture of elements to form a unique material. Brass is a mixture of copper
and zinc and the percentage of each element depends on the desired material. It
has a higher malleability than bronze or zinc. Meaning that it can be bend
easily into it desired form.</span>