I am a seven-letter word but if you remove four of my letters I will have one left. What word am I?

I am a type of food that is often found in the fridge and can be white in colour. What I am?
Hint 1: I am a dairy product.
Hint 2: You can spread me on the bread.

What is more useful when it is broken?

When I get multiplied by any number, the sum of the figures in the product is always me. What am I?

Can you find the missing piece of the Porsche?

What is the Surname of Barbie Doll?

I am soft and cuddly that soothe your heart. But, If you pick my last name I am going to tear you all apart. Who am I?

Count the number of times the letter "F" appears in the following paragraph:

FAY FRIED FIFTY POUNDS OF
SALTED FISH AND THREE POUNDS
OF DRY FENNEL FOR DINNER FOR
FORTY MEMBERS OF HER FATHER'S FAMILY.

It comprises roots which nobody sees,
Much taller than those trees,
Up and up it goes,
Still it never grows?

When I go in I might cause pain. I cause you to spit and ask you not to swallow. I can fill your hole. What am I?