standard_description: Know relative sizes of measurement units within one system of units including km, m, cm; kg, g; lb, oz.; l, ml; hr, min, sec. Within a single system of measurement, express measurements in a larger unit in terms of a smaller unit. Record measurement equivalents in a two column table. For example, know that 1 ft is 12 times as long as 1 in. Express the length of a 4 ft snake as 48 in. Generate a conversion table for feet and inches listing the number pairs (1, 12), (2, 24), (3, 36), ...
problem_activity: Solve. Show or explain your work.
a.
$$\begin{align} 7,396 \\ {–\ 2,145}& \\ \hline \end{align}$$
b.
$$87,625-5,031=$$
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c.
$$\begin{array}{r} &19,850\\ -\!\!\!\!\!\!&15,761\\ \hline \end{array}$$


aligns: no