What is the tightest asymptotic bound for this recurrence? $$T(n) = T\left(\frac{n}{2}\right) + T\left(\frac{n}{4}\right) + T\left(\frac{n}{8}\right) + n$$

How do you solve this recurrence?
It will be $\Theta(n)$, to save myself from rewriting an entire answer, I will refer you to this question and you can apply the answer to your question.