Estimates from different sources vary, but it is generally thought that, globally, about how many people die from starvation and/or complications related to malnutrition every year?

With respect to vehicles, what does the abbreviation “CAFE” stand for?

Which is an example of a conditionally renewable energy resource?

The U.S. currently makes up approximately what percent of the world’s total population?

Globally (at the current rate of deforestation) approximately what percent of tropical rainforest will be destroyed by 2050?

What Law of Physics states that when energy is converted from one form to another, some of it is always transformed to less usable or unusable energy?

If a parcel of air has a temperature of 15ºC and a specific humidity of 2g/kg, its capacity would be _____ and the relative humidity would be _____. 

What is the world’s human population projected to be in 2050?

Pollination and pest control are examples of ecologic services provided by living things.

What do we call a species on which other species in an ecosystem largely depend, such that if it were removed the ecosystem would change drastically?