Answer to Question 1
The corporation issuing a bond or a stock is the seller in a primary market, while anyone who holds a stock or bond can sell in the secondary market.
Answer to Question 2
The government provides healthcare services because the marginal social benefit of healthcare exceeds the marginal benefit perceived by its consumers, Consumers underestimate the benefit of healthcare because they underestimate the health risks they face. They also underestimate their future needs for healthcare. And some people cannot afford the healthcare they need. For these reasons the majority of voters want healthcare to be available on need rather than on the ability and willingness to pay
Annual net primary productivity on Earth.
Illustration showing how the primary breast tumor metastasized through the lymphatic and blood vesse
The Secondary Mirror Does Not Create a Hole in the Image
The b sheet, another common secondary structure in proteins
One Module of the Primary Visual Cortex
Primary growth in a root