For the first one it is C the muscle system
For the second one it is A allow movement in the body
For the third one it is C Skeletal Muscles
Answer: 5.5
Explanation: Strontium titanate is both much denser (specific gravity 4.88 for natural, 5.13 for synthetic) and much softer (Mohs hardness 5.5 for synthetic, 6–6.5 for natural) than diamond.
It should remain constant because of the law of conservation of mass and because the flask is sealed no mass will escape
