Answer:The value of the underlined digit is 50Step-by-step explanation:Place values are simply what a digit represent in a number. The value of a digit is always determine by its position of that digit in a number.For example; In the number 45678, to determine the place value, you will start from the left: 8 stands for ones or unit7 stands for 7 ten or 706 stands for 6 hundred or 6005 stands for 5 thousand or 50004 stands for 4 ten thousand or 40000But when dealing with decimal fraction e.g 0.123After any decimal fraction, you determine the place value starting from the right. That is:1 stands for 1 tenth or 1/102 stands for 2 hundredth or 1/2003 stands for 3 thousands or 3/1000In this question: 56.13 which is our main concern, there are digits whose position are before the decimal point( that is the whole number) and there are digit whose position are after the decimal point ( the decimal number),To determine the place value of the whole number you are to start from your left but to determine the place value of the decimal number, start from your right.In 56.131 stands for 1 tenth or 1/103 stands for 3 hundredths or 1/1006 stands for 6 unit or 6 one5 stands for 5 tens or 50Therefore the place value of the underlined digit '5' stands for 50