The Mongols spread the use of gunpowder.The Mongols controlled both China and Russia.<span>Pax Mongolica encouraged trade along the Silk Road. I would honestly say these are the main effects of the Mongol incursion into Europe and Asia plus the inadvertent introduction of the bubonic plague of infected rats from Asia to Europe.</span>
The answer is A, four weeks (the lunar cycle is about 29.5 days).
The scientific method<span> is illustrated by the acceptance of the copernican model of the universe over the ancient Greek ptolemaic model. In turn, this advance led to Kepler's discovery of the laws of </span>planetary motion<span> and Newton's discovery of the law of gravity. so basically it was about testing different theories over and over again.</span>
