(Undated)  --  Two Minnesota manufacturers might be considered an accurate barometer of improved corporate financial conditions nationwide.  Many companies such as 3M are riding a wave of higher sales and revenues.  On Monday, the Maplewood-based manufacturer predicted its second-quarter sales will beat analysts' estimates.  Meanwhile, Golden Valley-based General Mills is now offering what many other companies are these days, higher dividends for investors based on having plenty of cash on hand.