Update exercises/square-root/introduction.md

Co-authored-by: Anastasios Chatzialexiou <[email protected]>

Author: xanni

exercises/square-root/introduction.md

@@ -5,6 +5,6 @@ We are launching a deep space exploration rocket and we need a way to make sure
 As the first step in our calculation, we take a target number and find its square root (that is, the number that when multiplied by itself equals the target number).
 
 The journey will be very long.
-To make the batteries last as long as possible, we had to make our rocket’s onboard computer very power efficient.
-Unfortunately that means that we can’t rely on fancy math libraries and functions, as they use more power.
+To make the batteries last as long as possible, we had to make our rocket's onboard computer very power efficient.
+Unfortunately that means that we can't rely on fancy math libraries and functions, as they use more power.
 Instead we want to calculate the square root directly.