The dot plot shows the mass, in grams, of several substances in an experiment. how many substances has their mass recorded during the experiment? enter the answer in the box.

a number line ranging from 60 to 68 with four dots over 64, one dot over 65, two dots over 66, two dots over 67, and four dots over 68.

The number of substances that were recorded are:

13

Step-by-step explanation:

We are given a number line that represents the number of substances with their mass recorded during the experiment.

We make the frequency table with the help of this data:

Interval                   Frequency

64                                  4

65                                   1

66                                   2

67                                    2

68                                   4

Hence, the number of substances that were recorded in the experiment is equal to the total frequency from the table.  

i.e.  4+1+2+2+4=13

Hence, number of substances that were recorded are:

13