Select the correct answer from each drop-down menu.

brass and bronze are both of copper because copper is the component in brass and bronze.

a.
alloys
composites
variations
void

b.
main
most dense
most expensive
only

Brass and bronze are both alloys(A) of copper because copper is the main(B) component in brass and bronze.

Explanation:

Brass and Bronze are used in our day to day life known as metal alloys.  Brass is an alloy of the metals like copper and zinc which has high percentage of metal copper with tin combined with it.  

Brass is dull yellow in color. Bronze is reddish brown in color. Brass was known to be present in 500 BC. Bronze was about 3500 BC known to be present.  Thus Bronze and Brass are both alloys of the metal copper since the main component in the brass and bronze is copper.

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