controlled assessment! - ISA

hi guys,
i am doing ISA in a weeks. Its AQA core science.
my hypothesis is: 'how much vitamin c is in food depends upon the time the food is cooked for'
Context is (in short words) its i need to tell hospitals that raw vegetable has higher content of vitamin c than boiling the vegetable.
my chosen vegetable is broccoli

i really need help with variables what are the variables? ( i know what they mean and control is the same and independent is the one you change and dependent one) please help me to figure out what are my variable for the experiment. And i doing this experiment using DCPIP.
i am doing the research sheet,
i don't know what to put on the risk assessment issues and context
please help find the variable and maybe which graph to use ( i think its line graph) and please help with risk assessment.
thank YOu i have been researching for more than 5 fives but can't find any helpful ANSWERS
THANK YOU!

Hey I am doing that experiment but the context is different.Your teacher may give you a low grade but beware on the results day the isa grade may be higher.In the physics isa my teacher told me that I got a c grade but when I got my results I got an A*!How did that happen?I can't tell you the variables because the research task is independent work!sorry!

wow congrats on your A*
and its ok and i understand and finally of researching for almost 2 weeks i get what my variables are:!
my teacher give me a check list as h/wk too help us with isa and i did all the questions except one which i don't get. can you help me on that plz?
its how do we know that patients are really getting the right level of vitamin c if there food is cooked.
Also if you don't mind can you explain what is the context on the research sheet. you know where it says relating the investigation to the context. i dont know what you to put there!
n Thanks

Thanks.YOur teacher needs t give you the context!by the way are you in yr 11?I think I had got that A* because the examiner marked mine again because the teacher marked our isa so harshly and mine was the highest score so they had moderated mine and other isa scripts!

abit of misunderstanding their, sorry! i have the context but you know the research sheet the last box where it says relating the investigation to the context. the title of that box is context. That's what i am talking about
btw no, i am in year 10.
how can i relate it to the context?

In the context box you just write in something that relates to real life.I remember In the physics isa I did an isa based on pendulums.The context was 'the swing manufacturers can measure the amount of strings to work out the oscillations.THE SWING SHOULDN'T SWING TOO HIGH BECAUSE A SMALL CHILD CAN FALL OFF IT.I wrote something like that.....