Change something in a script with other script

Hello!

( Sorry for the bad english in this entire text )

I have a plane ( water ) that raises by time.
This is the script for the raising water:

using UnityEngine;
using System.Collections;

public class WaterRise : MonoBehaviour {

public Vector3 raisespeed = new Vector3(0,5.0f,0);

// Use this for initialization
void Start () {
      
}

// Update is called once per frame
void Update ()
{
	//	WaitForSeconds(5);
transform.Translate(raisespeed * Time.deltaTime);
}
}

This is the WaterRise script. And it works. Now i have an other script, the MainMenu script. These are all written in c#. So, i have a toggleabble ‘‘radio button’’ in the MainMenu script. I want to increase the value of ‘‘raisespeed’’ ( so the plane moves faster ). How can i do this? I can’t figure out how to change the values of a script with other script. I want to change the Vector3(0,5.0f,0)
This is the script for the MainMenu ( i know its not actually a main menu ):

using UnityEngine;
using System.Collections;

public class MainMenu : MonoBehaviour {

	private bool fastmode = false;

	void OnGUI () {
		fastmode = GUI.Toggle (new Rect (25, 25, 100, 30), fastmode, "Fast mode");
	}
	void Update () {
	    if (fastmode == true) {
	     WaterRise = GetComponent("WaterRise") as WaterRise;
	     WaterRise.do public Vector3 speed = new Vector3(0,5.0f,0);
		}
	}
}

This code is a totally fail now.

Thanks for helping!

EDIT: I didn’t notice they were in different scenes. To fix this you will need to change your MainMenu to say something like:

void Start()
{
    PlayerPrefs.SetInt("raisespeed", 5);
}
void OnGUI () {
    fastmode = GUI.Toggle (new Rect (25, 25, 100, 30), fastmode, "Fast mode");
    if(GUI.changed && fastmode == true)
        PlayerPrefs.SetInt("raisespeed", 10);
    else if(GUI.changed && fastmode == false)
        PlayerPrefs.SetInt("raisespeed", 5);
}
void Update () {

}

Then change your waterrise script to be:

public Vector3 raisespeed;
 
// Use this for initialization
void Start () {
     raisespeed = new Vector3(0, PlayerPrefs.GetInt("raisespeed"), 0);
}

That will do it for you.

More info on playerprefs can be found here: Unity - Scripting API: PlayerPrefs