If integers ending in zero are excluded, what is the unit digit of the product of the even integers from 102 to 198, inclusive?
Pick one.
A) 6  B) 5  C) 4  D) 3  E) 2
102 x 104 x 106 x 108 =&gt; unit digit 4   112 x 114 x 116 x 118 =&gt; unit digit 4   192 x 194 x 196 x 198 =&gt; unit digit 4   So we have 10 numbers ending by 4 to multiply.   Given that 4 x 4 = 16, we have 5 numbers ending by 6 to multiply   Given that 6 x 6 = 36, we have 3 numbers ending by 6 to multiply   So the unit digit is 6   6nswer: 6
<result>A</result>
If integers ending in zero are excluded, what is the unit digit of the product of the even integers from 102 to 198, inclusive?