Shares of First Solar Inc. FSLR dropped as much as 7% in the extended session Thursday after the solar company reported first-quarter earnings that missed expectations and sales that also missed and were nearly halved. First Solar earned $45.6 million, or 40 cents a share, in the quarter, contrasting with a loss of $43.3 million, or 41 cents a share, in the year-ago period. Sales fell to $548 million, from $1 billion, mostly driven by a drop in the volume of solar modules sold to third parties, the company said. Analysts polled by FactSet expected EPS of 99 cents on sales of $714 million in the quarter. The company kept…