Question

(2.5×10^−10)(7×10^−6)
Express your answer in scientific notation.
A. 1.75×10^16
B. 1.75×10^−15
C. 1.75×10^−16
D.1.75×10^−17

Answer 1

(2.5×10^−10)(7×10^−6) 
= (2.5 x 7) (10^−10 x 10^−6)
= 17.5 x 10^-16
= 1.75 x 10^-15

answer
B. 1.75×10^−15