Quiz 2

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You have up to 25 minutes. You may use a calculator, but no text book, notes, or network.

Use the hexadecimal codes in the right column to fill in the 8×8 icon grid, assuming 1 bit per pixel.

It’s an ampersand (‘and’ symbol) from an 8×8 pixel font.
If an image uses 5 bits per pixel, what is the maximum number of colors it can contain?

With 5 bits per pixel, we can have 2⁵ colors, and 2⁵ = 32.
Suppose you work for a CPU manufacturer that has exhausted its supply of XOR gates. Show whether or not the expression $A\cdot B' + A'\cdot B$ is equivalent to $A\oplus B$ by completing a truth table of all possible values of inputs $A$ and $B$ .

They are the same. Below is the truth table that proves it. You do not need to write the circuit diagram shown above the table – that’s just a convenient way to show how each column is calculated.

Truth table

Recall that XOR is a way to say “not equal to.” Its result is true when A and B are different.