https://www.youtube.com/watch?v=DwVyvOzxDno
Si+ (deals with "how" and "what" questions):
"An atom is the smallest constituent unit of ordinary matter that has the properties of a chemical element. Every solid, liquid, gas, and plasma is composed of neutral or ionized atoms. Atoms are very small; typical sizes are around 100 picometers (a ten-billionth of a meter, in the short scale).
Atoms are small enough that attempting to predict their behavior using classical physics – as if they were billiard balls, for example – gives noticeably incorrect predictions due to quantum effects. Through the development of physics, atomic models have incorporated quantum principles to better explain and predict the behavior etc."
Si- (deals with "why" questions):
"The United States became the world's leading industrial power at the turn of the 20th century...
...due to an outburst of entrepreneurship in the Northeast and Midwest and the arrival of millions of immigrant workers and farmers from Europe. The national railroad network was completed and large-scale mining and factories industrialized the Northeast and Midwest etc."
Ti+ (deals with "how" and "what" questions):
"Uniflow engines attempt to remedy the difficulties arising from the usual counterflow cycle where, during each stroke, the port and the cylinder walls will be cooled by the passing exhaust steam, whilst the hotter incoming admission steam will waste some of its energy in restoring working temperature. The aim of the uniflow is to remedy this defect and improve efficiency by providing an additional port uncovered by the piston at the end of each stroke making the steam flow only in one direction. By this means, the simple-expansion uniflow engine gives efficiency equivalent to that of classic compound systems with the added advantage of superior part-load performance, and comparable efficiency to turbines for smaller engines below one thousand horsepower. However, the thermal expansion gradient uniflow engines produce along the cylinder wall gives practical difficulties. The Quasiturbine is a uniflow rotary steam engine where steam intakes in hot areas, while exhausting in cold areas."
Ti- (deals with "why" questions):
"As pointed out in the introduction, if c denotes the length of the hypotenuse and a and b denote the lengths of the other two sides, the Pythagorean theorem can be expressed as the Pythagorean equation:"
a2 + b2 = c2 .... but why? ... see attached image.
Pythagoras proof.png