Answer: 
Explanation:
According to the law of conservation of mass, mass can neither be created nor be destroyed. Thus the mass of products has to be equal to the mass of reactants. The number of atoms of each element has to be same on reactant and product side. Thus chemical equations are balanced.
The balanced chemical equation for reaction of potassium superoxide with carbon dioxide to produce oxygen and potassium carbonate will be:

Explanation:
The force of gravity acting on an object is given by :
W = F = mg
Where W is the weight of an object
The force of gravity on house is 300,000 N. The force of gravity pulling down on your house would be exactly twice as much if your house has twice as much as mass because force of gravity is directly depends on mass.
Answer:
Well, it could be B or D but I would say B.
Explanation:
The structure of an organelle is usually fit to its function so it is most likely B.
Hope this helps!
This year course engages students in becoming skilled readers of prose written in a variety of periods, disciplines, and
rhetorical contexts and in becoming skilled writers who compose for a variety of purposes. More immediately, the course
prepares the students to perform satisfactorily on the A.P. Examination in Language and Composition given in the spring.
Both their writing and their reading should make students aware of the interactions among a writer’s purposes, audience
expectations, and subjects as well as the way generic conventions and the resources of language contribute to effectiveness
in writing. Students will learn and practice the expository, analytical, and argumentative writing that forms the basis of
academic and professional writing; they will learn to read complex texts with understanding and to write prose of
sufficient richness and complexity to communicate effectively with mature readers. Readings will be selected primarily,
but not exclusively, from American writers. Students who enroll in the class will take the AP examination.