Answer:
a: 34%
b: couldn't find the answer
Step-by-step explanation:
first we put the radius as r
we know surface area is 4pirsquared
so then we minus percent which is 119 so it is 81/100
square that fraction which will result 6561/10000
now we put in and equation of 4pirsquared -4pirsquared multiply 6561/10000 divide this all by 4pirsquared to get 3439/10000 or 0.3439 change it to %
34.39%