Earth Science, Engineering

CK-12-Earth-Science.md

"CK-12 Earth Science for Middle School"

• percent
• range - 3-8 miles
• minus
• divide - 1/1,000 - is this different from fraction? "one thousandth"
• equals
• pH

Units

• 2.57 cm/day
• 3,700 m
• (3.0 g/cm^3)
• astronomical-unit 53 AU
• "such-that" use of dash -, NOT minus:
  • 1:24,000 scale - 1 inch = 2000 ft
• currency - $100
• celsius - 900°C
• fahrenheit - -212° F
• 23 terawatts (2.3 x 1013 W)
• degrees - 23 1/2°
• atmosphere - atm
• north - 30° N
• in a table heading - (km/hr)

Properties

• :chemical-formula

Not MathML?

• seventeen-hundreds - in the 1700s
• "or" slash - 27 km (16.7 miles/88,580 ft)
• "or" parens - 1,100 km/h (700 mph).

enineering-intro-k12.md

Engineering: An Introduction for High School

• time? - 300 BC, AD 300
• percent and range - 3-4% - "3 to 4 percent"
• size "by" - $3^{\prime\prime} \times 5^{\prime\prime} \times 1^{\prime\prime}$ - 3 inches by 5 inches by 1 inch
• year - $'55$ World Series

Units

• parts-per-billion - 15 ppb
  • parts-per notation
• pH (potential-of-hydrogen)
• currency - $63.1 billion

Properties

• :chemical-formula

Not MathML?

• (1957-) - "1957 to present day"