Questions

Because arteries have to have thick walls for use of protection. Its when you get to veins where the walls get thinner. And the use of the heart is to pump blood to all of the cells and organs in the body so it would be to transport blood away from the heart.

i.e. 

Arteries = Away from the Heart 
Veins = Back to the Heart.

Starting with the top 3 digit number, the first digit increases by 2 as you descend,from 1 to 11. The middle digit decreases by 1 each time,and the right hand digit alternates between 5 and 3

1.Hardware abstraction layer

2.Kernel

3.Subsystems

4.System Services.

From the given data,

1 + 9 + 8 = 1

ONE + NINE + EIGHT

Consider the first letters and join them viz O N E = 1

So, now consider 2 + 8 + 9 in similar way

TWO+EIGHT+NINE

First letters are T E N = 10

2 + 8 + 9 = 1⃣0⃣