R u smart?

Science:

1) A stone is thrown up into the sky. What will happen to the potential energy and kinetic energy of the stone before it reaches the highest point?
A. Potential energy decrease, kinetic energy increase.
B. Potential energy increase, kinetic energy unchanged.
C. Potential energy increase, kinetic energy decrease.
D. Potential energy unchanged, kinatic also unchanged.

2) What substances can be given to as a relief for gastric pain?
A. Potassium hydroxide B. Sodium hydroxide
C. Magnesium hydroxide D. Vitamin C

3) A plastic bottle filled with warm water is tightly closed and left in a refrigerator for a few hours. The bottle collapses due to
A. an increase in air pressure in the bottle.
B. a decrease in air pressure in the bottle.
C. a decrease in air pressure in the refrigerator.
D. an increase in air pressure in the refrigerator.




answer : 1) C 2) C 3) B