GetComponent

Question 1

private Rigidbody playerRb;

public float gravityModifier;

Answer 1

void Start()
{
playerRb = GetComponent< Rigidbody > ();
Physics.gravity*=gravityModifier;
}

Question 2

private float repeatWidht;

Answer 2

void Start () 
{
repeatWidht = GetComponent < BoxCollider >().size.x /2;

}

Question 3

private Animator playerAnim;

Answer 3

(Start) playerAnim = GetComponent < Animator >();

(Update) playerAnim.SetTrigger(“Jump_trig”);