Notice that the dividend $(80)$ is a whole number ending in a zero.

To divide a whole number ending in zero by $10,$ we remove the final zero as follows: \begin{align*} \require{cancel} 80 \div 10 &= \\[5pt] 8\!\cancel{0} &= \\[5pt] \bbox[3pt,Gainsboro]{\color{blue}8}& \end{align*}

Notice that the dividend $(4,200)$ is a whole number ending in a zero.

To divide a whole number ending in zero by $10,$ we remove the final zero as follows: \begin{align*} \require{cancel} 4,200 \div 10 &= \\[5pt] 4,20\!\cancel{0} &= \\[5pt] 420& \end{align*}

Notice that the dividend $(20,000)$ is a whole number ending in a zero.

To divide a whole number ending in zero by $10,$ we remove the final zero as follows: \begin{align*} \require{cancel} 20,000 \div 10 &= \\[5pt] 20,00\!\cancel{0} &= \\[5pt] \bbox[3pt,Gainsboro]{\color{blue}2,000}& \end{align*}

To determine the number of lollipops each kid receives, we need to calculate the value of

\[ 50 \div 10. \]

Notice that the dividend $(50)$ is a whole number ending in a zero.

To divide a whole number ending in zero by $10,$ we remove the final zero as follows:

\begin{align*} \require{cancel} 50 \div 10 &= \\[5pt] 5\!\cancel{0} &= \\[5pt] 5& \end{align*}

Therefore, each kid receives $5$ lollipops.

To determine the number of cars parked in each parking lot, we need to calculate the value of \[ 2,100 \div 10. \]

Notice that the dividend $(2,100)$ is a whole number ending in a zero.

To divide a whole number ending in zero by $10,$ we remove the final zero as follows: \begin{align*} \require{cancel} 2,100 \div 10 &= \\[5pt] 2,10\!\cancel{0} &= \\[5pt] 210& \end{align*}

Therefore, $210$ cars are parked in each parking lot.

Notice that the dividend $(49,000)$ is a whole number ending in two zeros.

To divide a whole number ending in two zeros by $100,$ we remove the final two zeros as follows: \begin{align*} \require{cancel} 49,000 \div 100 &= \\[5pt] 49,0\!\cancel{00} &= \\[5pt] 490& \end{align*}

Notice that the dividend $(590,000)$ is a whole number ending in two zeros.

To divide a whole number ending in two zeros by $100,$ we remove the final two zeros as follows: \begin{align*} \require{cancel} 590,000 \div 100 &= \\[5pt] 590,0\!\cancel{00} &= \\[5pt] 5,900& \end{align*}

Notice that the dividend $(230,000)$ is a whole number ending in three zeros.

To divide a whole number ending in three zeros by $1,000,$ we remove the final three zeros as follows:

\begin{align*} \require{cancel} 230,000 \div 1,000 &= \\[5pt] 230,\!\cancel{000} &= \\[5pt] 230& \end{align*}

Notice that the dividend $(2,500,000)$ is a whole number ending in three zeros.

To divide a whole number ending in three zeros by $1,000,$ we remove the final three zeros as follows:

\begin{align*} \require{cancel} 2,500,000 \div 1,000 &= \\[5pt] 2,500,\!\cancel{000} &= \\[5pt] 2,500& \end{align*}