Simple riddles

I hiss. I can be poisonous. I am long. I have a forked tongue. What am I?

I look flat, but I am deep, Hidden realms I shelter. Lives I take, but food I offer. At times I am beautiful. I can be calm, angry and turbulent. I have no heart, but offer pleasure as well as death. No man can own me, yet I encompass what all men must have.

There was a railroad crossing without any cars and trucks! Can you spell that without using any "R"?

Beth's mother has three daughters. One is called Lara, the other one is Sara. What is the name of the third daughter?

I have keys but no locks. I have a space but no room. You can enter, but can't go outside. What am I?

I have no life, but I can die, what am I?

You are on your way to visit your Grandma, who lives at the end of the valley. It's her anniversary, and you want to give her the cakes you've made. Between your house and her house, you have to cross 5 bridges, and as it goes in the land of make believe, there is a troll under every bridge! Each troll, quite rightly, insists that you pay a troll toll. Before you can cross their bridge, you have to give them half of the cakes you are carrying, but as they are kind trolls, they each give you back a single cake. How many cakes do you have to leave home with to make sure that you arrive at Grandma's with exactly 2 cakes?

I am the black child of a white father, a wingless bird, flying even to the clouds of heaven. I give birth to tears of mourning in pupils that meet me, even though there is no cause for grief, and at once on my birth I am dissolved into air. What am I?

When you don't have me, you want me, but when you do have me, you want to give me away. What am I?

What has four legs, but can't walk?