Respuesta :
The correct instruction for creating an array a of 20 elements of double is int a[n];.
What is an array?
An array is a group of related data elements kept in close proximity to one another in memory. The sole way to retrieve each data element directly is by using its index number, making it the most basic data structure.
There is no need to declare separate variables for each subject, for example, if we wish to keep a student's grades across five disciplines. Instead, we can create an array that will keep the data pieces in close proximity to one another in memory.
The high-precision floating-point data or numbers are stored using the C double data type (up to 15 to 17 digits). Large decimal number values are stored there. The amount of data that can be stored in values is double what can be stored in float data. It is called a double data type as a result.
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