Use the formula for the surface area of a right cone:

Where 'r' is the radius and 's' is the slant height, plug in what we know(use 3.14 to approximate for pi):

Multiply and simplify exponent:

Multiply:

Add, round to the nearest whole number:
Look up this site called calculator soup it gives great answers
Use desmos hope that helps
4. 6/8, 5. 3 5/8, 6. 7 7/8, 7. 72 months and 2,190 days