Which of these can be categorized as a secondary economic activity? A) teaching
B) healthcare
C) coal mining
D) textile production

What type of aid does nigeria receive? short term, tied, voluntary, bilateral, multilateral or long-term?

Why is the huronian supergroup rock formation particularly interesting to scientists? because it looks like a cross-section of a giant, stone encyclopedia because it formed during the period when oxygen began to accumulate in the atmosphere because it contains unusually large amounts of oxygen and sulfur because it dramatically altered the planet's development when it first formed

Match the mountains with the type of collision that formed them. a. andes b. aleutians c. north american cordillera d. appalachians 1. continental- continental 2. continental- oceanic 3. oceanic- oceanic 4. arc- continent