Digital Images of Io The accompanying picture of Jupiter’s moon Io is a digital picture, c...

Digital Images of Io The accompanying picture of Jupiter’s moon Io is a digital picture, created by using a rectangular pattern of small pixels. This image is 500 pixels wide and 400 pixels high, so the total number of pixels in it is 500 · 400 = 200,000 pixels. (Source: NASA.)

(a) Find the total number of pixels in an image 400 pixels wide and 500 pixels high.

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(b) Suppose that a picture is x pixels wide and y pixels high. What property states that it has the same number of pixels as a picture y pixels wide and x pixels high?