Which table represents a linear function? x---y
0---1
1---2
2---4
3---8

x---y
0---0
1---1
2---3
3---6

x---y
0---0
1---1
2---0
3---1

x---y
0---1
1---3
2---5
3---7

How many 3-digit numbers can you write using only digits 1 and 7? (of course, digits can repeat.) how many 3-digit numbers can you write using only digits 1 and 7? (of course, digits can repeat.)