Simplify -2/3-3/5

a)-1/15

b)-19/15

c)-2/5

d)-5/8

In the diagram, bc¯¯¯¯¯∥de¯¯¯¯¯ . what is ce ? enter your answer in the box.

Im so bad at fractions they are not my best math thing to work on

The relative growth rate for a certain type of fungi is 60% per hour. a small culture has formed and in just 6 hours the count shows to be 20,273 fungi in the culture. what is the initial number of fungi in the culture?