A certain influenza virus is spherical, with a diameter of 100nm. It is known that 1nm = 10 ^ - 7cm, so how many influenza viruses is 1cm ^ 3 in size? (results expressed by scientific counting method, the volume formula of the sphere is v = 4 / 3 π R ^ 3, π is 3.14)

A certain influenza virus is spherical, with a diameter of 100nm. It is known that 1nm = 10 ^ - 7cm, so how many influenza viruses is 1cm ^ 3 in size? (results expressed by scientific counting method, the volume formula of the sphere is v = 4 / 3 π R ^ 3, π is 3.14)

1 * 10 ^ 7 / [4 / 3 * 3.14 * (100 / 2) ^ 3] = 1.9 * 10 ^ 15

The diameter of a cold virus is 0.12 million meters, which is expressed by scientific notation______ Rice

000 000 12 m = 1.2 × 10-7 M

The diameter of a certain kind of pollen is about 30 microns. How many pollen grains can be connected up to 1 meter?
Expressed by scientific counting

1m = 10 ^ 6 μ M
10^6/30=10^5/3=3.333*10^4
So we need 3.333... * 10 ^ 4 of this pollen

Calculation: 1 / (A-2) - 4 / (square of A-4)=
Why is 1 / (A-2) - 4 / (a + 2) (A-2) equal to (a + 2-4) / (a + 2) (A-2)?

1/(a-2)-4/(a^2-4)
=1/(a-2)-4/(a+2)(a-2)
=(a+2-4)/(a+2)(a-2)
=1/(a+2)

Let's know that a is equal to 1 / 2, B is equal to negative 1, and find the value of the algebraic formula [a squared B minus 2Ab squared minus B3] divided by B minus [a plus b] [a minus b]

[a square B minus 2Ab square minus B3 power] divide B minus [a plus b] [a minus b] = [a square minus 2Ab minus B2 power] minus [a plus b] [a minus b] = - 2Ab = 1

1. Four out of nine divided by three out of four

(4/9) ÷ (3/4) = 16/27
Four out of nine divided by three out of four
Three quarters of sixteen out of twenty-seven is four out of nine

How to divide 7.83 into 9

7.83÷9=3×2.61÷9=3×3×0.87÷9=0.87

14.4 divided by 0.75

19.2

Minus 0.75 times minus 1.5 divided by minus four ninths equals,
Minus 0.75 times minus 1.5 divided by minus 4 / 9
Is it done according to the same number
Or based on the negative factor

Minus 0.75 times minus 1.5 divided by minus 4 / 9
=0.5÷（-4/9）
=-9/8

X 128 power + X 110 power - x 32 power + x 8 power + x 2 power - x is divided by X-1?

Let f (x) = (x-1) g (x) + R (x), where f (x) denotes the algebraic formula you give, and the remainder is R (x), then as long as x = 1 is substituted into the calculation, the remainder = R (x) = f (1) = 2 is obtained