Show that if you have three polarizing filters, with the second at an angle of 45 degrees to the first and the third at an angle of 90 degrees to the first, the intensity of light passed by the first will be reduced to 25% of its value. (This is in contrast to having only the first and third, which reduces the intensity to zero, so that placing the second between them increases the intensity of the transmitted light.)

Perhaps seek some professional ? it isn't very asking some children who are just trying to find out answers to homework.also, it seems professional would actually be good to you. obviously it isn't going to magically fix your depression, but it'll do something. drugs, smoking weed, it won't do much, especially if your husband is against it. if you do it he'll dislike it. but talk to him, try and get him to listen to you, and figure everything out together, okay? there's a website- maybe it can offer some ?