nights sleep?
how long do you believe it took you to fall asleep last night?
how long did it take you to fall asleep last night, when compared with a normal night?
how many times do you believe you woke from your sleep? we chose salt, sugar and oil.
we made sure it was a fair test by using the same amount of water, a spoonful of each substance and by mixing the water the same number of times.
we found that the salt and sugar mixed with the water but the oil did not - it floated to the top of the water. 