They speed up chemical reactions
The digestive system uses mechanical and chemical methods to break food down into nutrient molecules that can be absorbed into the blood. Once in the blood, the food molecules, including fat molecules, are routed to every cell in the animal's body.
Answer:
4x + 6y = 420
Explanation:
since x is number of child tickets and y is adult tickets, and $4 is the cost of child tickets and $6 is the cost of adult tickets, that eliminates A and D.
The question also states "for one day", so that elimates C, which C is the equation for two days.
This leaves 4x + 6y = 420
Answer:
3 types are recombination,mutation and immigration
THE CORRECT ANSWER IS BEAR