Short-selling. For each problem, determine whether there will be a margin call if the price goes up $10. For each problem, determine the price limit that triggers a call.

4) Price = $65

Shares = 450

Initial margin = 40%

Maintenance margin = 35% or .35

5) Price = $80

Shares = 725

Initial margin = 55%

Maintenance margin = 45% or .45

6) Price = $75

Shares = 500

Initial margin = 50%

Maintenance margin = 40% or .4