Suppose two competing railroad companies agreed to fix shipping rates at a level that benefited both. What is this kind of voluntary arrangement called? A holding company A monopoly A trust A pool

A trust

Explanation:

Two railroad companies agreeing to fix prices would be a form of trust (that is to say, subject to anti-trust laws), and more specifically, it would be both price-fixing and cartelization.

This is highly uncompetitive behaviour that is prohibited by US law. The reason is that competition is supposed to benefit the customers by the offering of more efficient services at lower prices, while price fixing and other turst practices do the opposite: they keep prices artificially high, and can lead to reductions in service quality, like in a monopoly market structure.

d) a constitutional amendment

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