The correct option is A 770
Given that,
radius of cone is 3.5 m.
Slant height of cone is 7 m.
Rate of painting is ₹ 10/m2.
We know that,
curved surface area of a cone =πrl
Now, cost of painting the tent
=Rate of painting×Curved surface area of tent
=10×227×3510×7
=₹ 770