Caterpillar’s sales rose in the first quarter as market conditions for the machinery company begin to improve and dealers increase their inventory levels. Revenue climbed to $11.89 billion from $10.64 billion thanks to increased sales volume driven by higher end-user demand and changes in dealer inventories. Dealers boosted inventories by $700 million during the first quarter compared with $100 million in the prior-year period. The performance easily beat the $11.05 billion in revenue analysts polled by Zacks Investment Research expected. Sales for the construction industries segment rose 27 percent. North American sales climbed slightly, with higher end-user demand driven mostly by residential construction. Sales of new homes surged 20.7 percent in March to the highest level since 2006, the Commerce Department reported last week. While sales of existing homes fell last month, it was because there are so few on the market and prices jumped 17.2 percent due to intense …