Questions 98 through 100 refer to the following introduction

How many lectures are there in the series?

Look at the picture mark number 5

Look at the picture mark number 4

Look at the picture mark number 2

Look at the picture mark number 9

Look at the picture mark number 8

Look at the picture mark number 7

Look at the picture mark number 3

Look at the picture mark number 6

Look at the picture mark number 10