Find km/h with Kinetic Energy and mass?

Question

Sorry for the picture the math formatting is very hard. I'm trying to answer the exercise 4 which asks for (title). The info given is: Kinetic energy: $6,73*10^-19$ Mass: $9,109*10^-31$ My problem isn't the question itself it's actually only what happens when it goes from one step to $sqrt(1,50*10^12)$ Again sorry for the formatting but I've been trying to do it for like an hour already. Unfortunately I can't post a picture. https://i.stack.imgur.com/ubVqn.jpg

Answer 1

It was just simplifying the expression: $$\sqrt{\frac{2\times6.73\times10^{-19}}{9.109\times10^{-31}}}=\sqrt{1.50\times 10^{12}}=1.22\times10^6 \text{ m/s}.$$