A student is given 10g of three different powders, M, N and P. He adds each powder to separate beakers containing 30cm3 of water and stirs five times. Here are his results 
A.some of the powder dissolves 
B.all of the powder dissolves
C.none of the powder dissolves
Which can power can be completely separated from the water by using only filttration 
A.M
B.N
C.P
D.None of the powders 

How long does it take the Earth to make one orbit of the Sun 
A.One day
B.One week
C.One month
D.One year

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