30.

There are:

16 1×1 squares
9 2×2 squares
4 3×3 squares
1 4×4 square (the whole shape)

Hence, 16 + 9 + 4 + 1 = 30.

Look at it upside down. Instead of changing the equation, you can change your perspective.

This is from Dan Brown’s novel, Origin.

Nobody. The Barber of Seville is a woman. Female barbers are rare, but they exist.

And for more fun with barbers, check out the Barber paradox.

34 times. These 17 instances will be visible twice in a 24 hour period.

1:11
2:22
3:33
4:44
5:55
10:00
11:10
11:11
11:12
11:13
11:14
11:15
11:16
11:17
11:18
11:19
12:22