It would seem that r correlates to line AC. So another name could be Line AC. Remember to put a line above the two letters to let people know it is a line. I hope this helps! =)
The last one
Step-by-step explanation:
The last one is dividing.
Answer:
6
Step-by-step explanation:
It is A and B I think hope it helps
we are given

now, we can find x , y and z components

Arc length calculation:
we can use formula


now, we can plug these values

now, we can simplify it




now, we can solve integral


now, we can plug bounds
and we get

so,
..............Answer