Task: Question Answering
Input (English): Problem: two spherical balls lie on the ground touching. if one of the balls has a radius of 9 cm, and the point of contact is 10 cm above the ground, what is the radius of the other ball ( in centimeters ) ?
Options: a. 50 / 4, b. 70 / 6, c. 80 / 7, d. 90 / 8, e. 100 / 9
Output (English): d