The average height of the four Torres towers is 800 feet. If the four

\(a_1\leq{a_2}\leq{a_3}\leq{a_4}\);

The average height of the four Torres towers is 800 feet: \(a_1+a_2+a_3+a_4=4*800\);

The median height of 900 feet: \(\frac{a_2+a_3}{2}=900\) --> \(a_2+a_3=1800\);

Substitute \(a_2+a_3=1800\) into \(a_1+a_2+a_3+a_4=4*80\):
\(a_1+1800+a_4=4*800\);
\(a_1+a_4=1400\).

To maximize \(a_1\) we should minimize \(a_4\). Minimum value of \(a_4\) is 900 (the median value), thus the maximum value of \(a_1\) is 1400 - 900 = 500.

Answer: C.

\(a_1\leq{a_2}\leq{a_3}\leq{a_4}\);

The average height of the four Torres towers is 800 feet: \(a_1+a_2+a_3+a_4=4*800\);

The median height of 900 feet: \(\frac{a_2+a_3}{2}=900\) --> \(a_2+a_3=1800\);

Substitute \(a_2+a_3=1800\) into \(a_1+a_2+a_3+a_4=4*80\): \(a_1+1800+a_4=4*800\) --> \(a_1+a_4=1400\).

To maximize \(a_1\) we should minimize \(a_4\). Minimum value of \(a_4\) is 900 (the median value), thus the maximum value of \(a_1\) is 1400 - 900 = 500.

Answer: C.[/quote]

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