By TOM KRISHER and DAVID HAMILTON (AP Business Writers) Tesla’s first-quarter net income plummeted 55%, but its stock price surged in after-hours trading Tuesday as the company said it would accelerate production of new, more affordable vehicles. The Austin, Texas, company said it made $1.13 billion from January through March compared with $2.51 billion in the same period a year ago. Investors and analysts were looking for some sign that Tesla will take steps to stem its stock’s slide this year and grow sales.