16. * 1 point if any tangent plane to the sphere x + ytz = 9 makes intercepts a,bc on the axes, then the vlue of ttis 1 (a)1 (c) 1/3 (b) 1. /2 (d) 1 /9 o a o b

16. * 1 point If any tangent plane to the sphere x + ytz = 9 makes intercepts a,bc on the axes, then the vlue of ttis 1 (a)1 (C) 1/3 (b) 1. /2 (d) 1 /9 O a O b O O d 8. 1 point The equation of the sphere, through the circle, x +y + z= 1and 2x+ 4y + 52= 1touching the plane z = 0 is? (a) x+y tzi-2x-4y- 5z + 5 = 0 (6) x+y tz t 2x + 4y + 5z +5 = 0 (c)x ty t zé-2x-4y- 52-5= 0 (d) x + y- z- 2x-4y -52 +5 = 0