3/4 of a sphere with a radius of 13

First fnd SA then times 3/4

SA of sphere=4pir^2

r=13

SA=4pi13^2

SA=4pi169

SA=676pi

times 3/4

SA=507pi

answer is 507pi squaer units

(if they want to evaluate or aprox, use 3.14 for pi and multiply 507 and 3.14)