Question

complete the following table. round each of your answers to 3 significant digits.

	food	energy content when eaten
		kcal	\\(\boxed{}\\)
	a raw carrot
	three ounces of cooked sirloin steak		240.
		kj	\\(\boxed{}\\)
	a cup of grapefruit juice
		kj	481.

Explanation:

Step1: Convert calories to kilocalories and kilojoules

• For a raw carrot:
• Given \(3.00\times10^{4}\text{ cal}\).
• To convert to \(kcal\): Since \(1\ kcal = 10^{3}\text{ cal}\), then \(3.00\times10^{4}\text{ cal}=\frac{3.00\times 10^{4}}{10^{3}}kcal = 30.0\ kcal\).
• To convert to \(kJ\): Since \(1\ kcal=4.184\ kJ\), then \(30.0\ kcal\times4.184\ kJ/kcal = 125.52\ kJ\approx126\ kJ\).
• For three ounces of cooked sirloin steak:
• Given \(240\ kcal\).
• To convert to \(cal\): Since \(1\ kcal = 10^{3}\text{ cal}\), then \(240\ kcal=240\times10^{3}\text{ cal}=2.40\times 10^{5}\text{ cal}\).
• To convert to \(kJ\): Since \(1\ kcal = 4.184\ kJ\), then \(240\ kcal\times4.184\ kJ/kcal=1004.16\ kJ\approx1.00\times 10^{3}\ kJ\).
• For a cup of grapefruit juice:
• Given \(481\ kJ\).
• To convert to \(kcal\): Since \(1\ kcal = 4.184\ kJ\), then \(481\ kJ=\frac{481}{4.184}kcal\approx115\ kcal\).
• To convert to \(cal\): Since \(1\ kcal = 10^{3}\text{ cal}\), then \(115\ kcal = 115\times10^{3}\text{ cal}=1.15\times 10^{5}\text{ cal}\).

Answer:

food	cal	kcal	kJ
three ounces of cooked sirloin steak	\(2.40\times 10^{5}\)	\(240\)	\(1.00\times 10^{3}\)
a raw carrot	\(3.00\times 10^{4}\)	\(30.0\)	\(126\)