Techs show improvement, boost U.S. markets
Deterrence appropriate factor in determining penalty says top court
Best results in almost three weeks
But investors cheered by Greenspan's comments that rate hike not imminent
North American stocks plunge after comments made to U.S. Senate
Markets finish week on positive note
Investors cosnumed by inflation and interest rate worries
Investors spooked by improving U.S. economy
Positive U.S. retail sales report stokes rate-hike fears