For Alphabet, search traffic on mobiles surpassed desktop traffic worldwide for the first time, while Amazon was able to boost margins, an area of concern, as its cloud business boomed. Microsoft’s growing emphasis on cloud computing under Chief Executive Satya Nadella also put the company on track successfully transition away from its slowing business that relies on sales of personal computers. Alphabet’s shares jumped 10.5 percent to a record high of $752.50 in early trading, adding about $50 billion to its market value.