Which of the following is not needed to make a model of the water cycle

. an energy source

. water

. a closed container

. a drain

his is the chemical formula for epinephrine (the main ingredient in adrenaline) : C9H13O3N A biochemist has determined by measurements that there are 33. moles of carbon in a sample of epinephrine. How many moles of nitrogen are in the sample?

Which day of the year has the shotest period of day light in the northern hemesphiere A. the spring equinox B. the summer solstice C. the fall equinox D. the winter solstice

The green pigment that absorbs light energy is Chlorophyll. true or false

If 57.0 g of b2o3 is added to 44.7 g of cl2 and 68.8 g of c, what is the theoretical yield of boron trichloride?

Which dinosaur was able to hold its prey in its mouth firmly due to teeth that curved backward?

Which of the following is not a source of air pollution related to human activities

Objects and substances in motion is I

If you were to remove an electron from a sodium atom that has eleven protons, what would be the electrical charge of the ion?

The atomic mass of fluorine in 19.0 amu, so the molar mass is?

A rod shaped organism with no nucleus commonly found in Garbage will most likely belong to which kingdom