Dalton’s law states that any given time the percentage of each of these (toxic?) gasses in the air we breathe it’s contribution.
People who ascend high altitudes experience Delton’s law when they try to breathe. Oxygen’s pressure decreases a total atmospheric pressure decreases in accordance with Dalton’s law.
They are kind of opposite processes. Chemical synthesis is execution of chemical reactions to make products. Like you take two substances, you put them together, they react and you have new a substance. For example.

here Sodium and Chlorine react to make a new substance which is Sodium Chloride.
Chemical decomposition is process of seperating a substance to different substances. There is a substance by a reaction this substance becomes two substances, Like : XY -> X+Y For example :
Answer: A bike
A bike is composed of various simple machines. It has a wheel and axle as one component, and it also has screws to hold the various parts together, along with levers and pulleys that are connected to the pedals. So all of these simple machine concepts work together to help transport the rider from point A to point B.
The other answer choices of screw, inclined plane, and lever, are fairly simple machines that don't have many things going on at once compared to a bike.
Answer:
the reason why Mars is red is because of its regolith, or surface material, contains lots of iron oxide — the same compound that gives blood and rust their hue
Answer: The equation for kinetic energy is 
Explanation:
Kinetic energy is the energy possessed by the virtue of object's motion. It is defined as the work needed to move a body of a given mass from rest to its velocity.
Mathematically,

where,
m = mass of the body
v = velocity of the body.
Hence, above equation relates kinetic energy to the mass and velocity of the body.