Question

Bacteria vary somewhat in size, but a diameter of 2.9 μm is not unusual.

Answer 1

Answer:

a) 6.4 x 10^-12 cm^3

b) 17 x 10^-6 mm^2

Explanation

a). The shape is assumed to be spherical The volume = volume of a sphere = \frac{4}{3} \pi r^3

3

4

πr

3

V = \frac{4}{3}*3.142* 1.15^3

3

4

∗3.142∗1.15

3

= 6.3715 μm^3

1 μm^3 = 10^-12 cm^3

6.3715 μm^3 = 6.3715 x 10^-12 cm^3

==> 6.4 x 10^-12 cm^3

Answer 2

Answer:

See below

Explanation:

Volume of a sphere = 4/3 pi r^3

   we are given diameter   r = 1/2 dia = 1.45 u-meter = 1.45 x 10^-4 cm

  4/3  pi (1.45 x 10^-4)^3 = 1.277 x 10^-11   cm^3    = VOLUME

 

1.45 u-meter = .00145 mm

Surface area = 4 pi r^2 =  4 pi (1.45 x 10^-3 ) ^2 = 2.64 x 10^-5 mm^2