What does $R$ represent in $EcoR\, I$?

Given below are two statements:
Statement $I:$
Restriction endonucleases recognise specific sequences to cut $DNA$,known as palindromic nucleotide sequences.
Statement $II:$
Restriction endonucleases cut the $DNA$ strand a little away from the centre of the palindromic site.
In the light of the above statements,choose the most appropriate answer from the options given below:

Western blotting technique was developed by:

Which enzyme removes nucleotides from the ends of $DNA$?

How many types of restriction enzymes are there?

Select the correct pair from the following: