Which statements describe ecosystems?
1. biodiversity is one way to judge the health of an ecosystem.
2. ecosystems must be balanced to survive.
3. a healthy ecosystem can support an unlimited number of life forms.
4. the parts of an ecosystem exist independently and have little to do with each other.
5. people's activities sometimes improve the health of an ecosystem
6. predators play a role in balancing the earth's ecosystems.

(2,20) means that the 2 is 2 hours and 20 is 20$. so there both 20$ for 2 hours only the same price. like it says. so, the dunk tank and the bounce house are the same price (20$) for the same amount of time (2 hours).

hope i

54 km / hours

step-by-step explanation:

we need to convert seconds to hours

60 seconds = 1 minutes

60 minutes = 1hour

15 m         60 second   60 minutes

  * *         = 54000 meters/ hour

second     1 minute             1 hour

now we need to convert meters to km

1000 m = 1 km

54000 m       1 km

*   = 54 km / hours

hour               1000m

the domain of a function is the set of input values, x , for which a function is defined. the domain is shown in the left oval in the picture below. the function provides an output value, f(x) , for each member of the domain.