In maintaining the large land empire of russia, what was arguably the main difficulty?

a. ethnic divisions
b. inexperienced leaders
c. lack of industrialization
d. lack of natural resources

This is what i did 45-5=4040÷4=10so there are 10 white marbles but am not sure is just a question that am not sure

The virus is considered to be are living item since they have hereditary material dnas or rnas. they can imitate and change. they respond to boosts, for example, radiation, chemicals, and warmth. they have antigenic properties. they are proficient to duplicate with a same hereditary constituent.