Answer:
3 machine
Step-by-step explanation:
It is given that 6 machine each working at the same rate can complete the work in 12 days
We the has to complete in 8 days
Let we need x extra machine to complete the work in 8 days
So total number of machines =x+6
Now according to man work day equation 



x=3 machine
Answer:
1 quintillion km
Step-by-step explanation:
do you know that you can put 100000 earths to sun to fill it
Answer:
C. -31m⁴n - 8m²
Step-by-step explanation:
Given:
(9mn - 19m⁴n) - (8m² + 12m⁴n + 9mn)
Required:
Determine an expression equivalent to it
Solution:
(9mn - 19m⁴n) - (8m² + 12m⁴n + 9mn)
Distribute the negative sign to open the parentheses
9mn - 19m⁴n - 8m² - 12m⁴n - 9mn
Combine like terms
9mn - 9mn - 19m⁴n - 12m⁴n - 8m²
-31m⁴n - 8m²
Therefore, -31m⁴n - 8m² is an equivalent expression of (9mn - 19m⁴n) - (8m² + 12m⁴n + 9mn)