निम्नलिखित में से कौन सी उपग्रह श्रृंखला भू-स्थैतिक कक्षा (geostationary orbit) में परिक्रमा करती है?

Prolonged exposure to extreme cold temperatures may result in tissue damage known as frostbite, which is categorized as a:

In the context of ecosystem energy dynamics, which of the following expressions correctly defines Net Primary Productivity (NPP)?