Answer:
1.035 × 10^11
Explanation:
You added 7.14 × 10^10 and 3.21 × 10^10
You got correct answer which is 10.35 × 10^10
But you went wrong in putting it in scientific notation!
It should be 1.035 × 10^11
(Hint: take a number 1 and put in form 0.1 × 10^1 = 1
putting 1 in form of 0.01 means its 0.01 × 10^2
So when you move the decimal point to the left the × 10^n becomes × 10^n+1 )