Question

unit #1: measurement & classification

1. 80 mg = g = kg
2. 1.9 l = ml
3. 8.2 km = cm
4. 125 ml = l
5. complete the table below.

volume
length
time
temperature
mass
unit
how we measure it (what do we use)

Explanation:

Step1: Unit conversion for mass

• For \(80mg\) to \(g\):

Since \(1g = 1000mg\), then \(80mg=\frac{80}{1000}g = 0.08g\)

• For \(80mg\) to \(kg\):

Since \(1kg=1000000mg\), then \(80mg=\frac{80}{1000000}kg=8\times10^{-5}kg\)

Step2: Unit conversion for volume

For \(1.9L\) to \(mL\):
Since \(1L = 1000mL\), then \(1.9L=1.9\times1000mL = 1900mL\)

Step3: Unit conversion for length

For \(8.2km\) to \(cm\):
Since \(1km = 1000m\) and \(1m=100cm\), then \(8.2km=8.2\times1000\times100cm=820000cm\)

Step4: Unit conversion for volume

For \(125mL\) to \(L\):
Since \(1L = 1000mL\), then \(125mL=\frac{125}{1000}L=0.125L\)

Step5: Completing the table

• Volume:
• Unit: liter (\(L\)) or milliliter (\(mL\))
• Measuring tool: graduated cylinder, beaker
• Length:
• Unit: meter (\(m\)), kilometer (\(km\)), centimeter (\(cm\))
• Measuring tool: ruler, tape - measure
• Time:
• Unit: second (\(s\)), minute (\(min\)), hour (\(h\))
• Measuring tool: clock, stop - watch
• Temperature:
• Unit: Celsius (\(^{\circ}C\)), Fahrenheit (\(^{\circ}F\)), Kelvin (\(K\))
• Measuring tool: thermometer
• Mass:
• Unit: gram (\(g\)), kilogram (\(kg\)), milligram (\(mg\))
• Measuring tool: balance

Answer:

1. \(0.08\) \(g\), \(8\times10^{-5}\) \(kg\)
2. \(1900\) \(mL\)
3. \(820000\) \(cm\)
4. \(0.125\) \(L\)

5.

	Unit	How we measure it (what do we use)
Length	\(m\), \(km\), \(cm\)	ruler, tape - measure
Time	\(s\), \(min\), \(h\)	clock, stop - watch
Temperature	\(^{\circ}C\), \(^{\circ}F\), \(K\)	thermometer
Mass	\(g\), \(kg\), \(mg\)	balance