800 because 80% of 800 is 640
Answer:

Step-by-step explanation:
The given polynomials are,

In polynomial addition and subtraction only like terms can be added or subtracted.
So,




Answer:
Step-by-step explanation:
option (d) 4hrs 40mins
2.4 because 4.8/2 is 2.4. 14.4/4 is also 2.4. Constant of variation is the unit rate