If the cash in an account falls below the maintenance margin, then a margin call is required to replenish the margin account to the maintenance margin account

What do economists mean when they discuss "scarcity"?

What will be an ideal response?

While the classicists believed that both velocity and output are stable, Keynesians believe:

A. velocity is stable and output is variable. B. velocity and output are both variable. C. output is stable and velocity is variable D. the same as the classical economists that both output and velocity are stable