Ineed on these questions i tried a lot of things of a sheet of notebook paper but i’m just not really smart: (

1) salt water + fresh water = total water

352,000,000 + (9 x 106) = total water

352,000,000 + 954 = total water

352,000,954 = total water

3.52000954 x 10⁸ = total water in scientific notation

2) 5.1 x 108 = land

550.8 = land

5.508 x 10² = land in scientific notation

3) water - land

352,000,954 - 550.8

= 352,000,403.2

= 3.520004032 x 10⁸

4)

2.3 x = 0.023

-3.648 x 10⁸ = -364,800,000

48,482

1.45 x = 0.0000145

note: ascending is from smallest to largest

-364,800,000 ---> 0.0000145 ---> 0.023 ---> 48,482

-3.648 x 10⁸ , 1.45 x , 2.3 x , 48,482

answer: .64

step-by-step explanation

set up the formula for standard deviation for this set of numbers, then simplify