Apple became a $4 trillion company under the leadership of Tim Cook. what happens now?

Following Apple’s co-founder, the famous Steve Jobs, was a tough task for CEO Tim Cook since he took the reins as the company’s leader almost 15 years ago. Cook will step down in September, Apple announced on April 20. John Ternes, Apple’s senior vice president of hardware engineering, will replace him. Ternes, 50, will face challenges of his own, including replacing the executive who led Apple to a…