pineapple riddles   

A fruit on a tree. A tree on a fruit.

My inside is yellow, sweet and juicy. My outside is much harder. My yellow part goes on a pizza from Hawaii. Who am i?

I am the fruit who takes 2 years to grow. Who am I?

I am a fruit, sharp from outside and yellow from inside. My name has "apple" in it. Who am I?

I am a fruit that is very spiky on the outside and yellow, soft and juicy on the inside. I have “APPLE” in my name, but I am not an apple! Who am i?

I have a hard, throny outside. My yellow inside is super sweet. Who am i?