3000000m, expressed by scientific counting method as (keep two significant numbers)

3000000m, expressed by scientific counting method as (keep two significant numbers)


3.0*10^6



The radius of the sun is about 69 660 km, which is expressed by scientific notation (with 3 significant numbers reserved) about______ Kilometers


69660 ≈ 6.97 × 104. A: About 6.97 × 104 km



Use scientific notation to express 0.000695 and keep two significant numbers as______ .


000695 = 6.95 × 10-4 ≈ 7.0 × 10-4