Answer:
Multiplying and simplifying the term
we get 
Option C is correct option.
Step-by-step explanation:
We need to multiply and simplify: 
Simplifying the term:

While multiplying, the variables with same bases are multiplied: 
In the given question only x^2 and x^4 are variables with same bases, So we get:

So, multiplying and simplifying the term
we get 
Option C is correct option.
Answer:
Step-by-step explanation:
3) (21²-6²)½ = 20.1 cm
4) (10²+7²)½ =12.2 cm
5) (6.5²-2.7²)½ = 5.9 cm
Answer:
Carlos has practiced piano for
hours.
Carlos needs to practice
hours.
Step-by-step explanation:
We have been given that Carlos wants to practice piano 2 hours each day. He practices piano for 3/4 hour before school and 7/10 hour when he gets home.
First of all, we will find piano practiced before school and after school by adding both amounts as:

Make a common denominator:


Add numerators:

Therefore, Carlos has practiced piano for
hours.
Now, we will subtract
from 2 find number of hours Carlos needs to practice to reach his goal.





Therefore, Carlos needs to practice
hours before going to bed in order to meet his goal.
315.
15 tens:150
2 hundreds: 200
150+200= 350