Given that 100.48 = x, 100.70 = y and xz = y², then the value of z is close to  Choose the correct option:
A) 1.2
B) 1.45
C) 2.2
D) 2.9
E) NOne
Sol.   xz = y² ⇔ (10 0.48 )z(100.70)2 (10 0.48z) = 10(2×0.70) = 101.40   ⇔ 0.48z = 1.40 ⇔ z= 140/48 = 35/12 = 2.9 (approx).   Answer 2.9
<result>D</result>
Given that 100.48 = x, 100.70 = y and xz = y², then the value of z is close to