Answer: this is our required factor i.e.

Explanation:
Since we have given that

As we know the identity , which says that

So, we can use this here ,

Hence this is our required factor i.e.

Answer:
4900
Square Root of 30: 5.47722557505- round it up
Step-by-step explanation:
70x70
7x7=49
add the 2 zeros at the end
4900