What happens when you try to compile the following code and execute the Dolphin application? Line Numbers $(1-12)$ are not parts of a code.

$($Multiple answers: Choose all that apply$)$

$1$ class AnimalO

$2$ class Mammal extends Animal

$3$ class $-$Cat extends Mammall

$4$ class Dolphin extends Mammal

$6$

$7$

$8$

$9$

$10$

$11$

$12)$

public static void main $($Stringi args$)$

Mammal m $=$ new Cat,

Animal a $=$ m

Dolphin d $=($ Dolphin$)$ a$,$