CNBC: U.S. tech companies were busy striking big deals last year. And they are showing no signs of slowing down in 2015, according to a report from PricewaterhouseCoopers. Some of the biggest deals last year included Facebook’s acquisition of WhatsApp. “As we consider the almost $350 billion in cash and securities on hand at the top 25 technology companies … 2015 promises to be another exciting year.’