The micrometer (1 μm) is often called the micron. (a) How many microns make up 3.0 km? (b) How many centimeters equal 3.0 μm? (c) How many microns are in 3.0 yd?

3 x 10⁻⁹km

3 x 10⁻⁴cm

2.73 x 10⁶μm

Explanation:

 A micron is a subunit of measurement usually for length dimensions.

                     1μm   = 1 x 10⁻⁶m

a. How many microns make up 3km;

         Now convert to meter first;

                 1000m  = 1km

           So, 3km will be made up of 3000m

So;

          1 x 10⁻⁶m    =     1μm  

         3000m  =     =   = 3 x 10⁻⁹km

b.  How many centimeters equal 3.0 μm?

            Since;

                        1μm   = 1 x 10⁻⁶m

                         3μm  = 3 x 1 x 10⁻⁶  = 3 x 10⁻⁶m

So;

            100cm  = 1m;

                  1m  = 100cm

             3 x 10⁻⁶m  = 3 x 10⁻⁶  x 10²   = 3 x 10⁻⁴cm

c. How many microns are in 3.0 yd?  

              1yd  = 0.91m

              3yd  = 3 x 0.91  = 2.73m

So;

            1 x 10⁻⁶m    =     1μm  

              2.73m will give   = 2.73 x 10⁶μm

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