The restriction enzyme $EcoRI$ cuts $DNA$ at the recognition site $GAATTC$ between which two bases?

Refer to the following statements for agarose-gel electrophoresis :
$(a)$ Agarose is a natural polymer obtained from sea-weed.
$(b)$ The separation of $DNA$ molecules in agarose-gel electrophoresis depends on the size of $DNA$.
$(c)$ The $DNA$ migrates from negatively-charged electrode to the positively-charged electrode.
$(d)$ The $DNA$ migrates from positively-charged electrode to the negatively-charged electrode.
Choose the most appropriate answer from the options given below :

The enzyme known as restriction endonuclease:

$Taq$ polymerase is isolated from a

Ligation of foreign $\text{DNA}$ at which of the following site will result in loss of tetracycline resistance of $\text{pBR}^{322}$?

Which restriction enzyme produces blunt ends upon cleavage?