Answer:
Implicit type casting means the type casting done by the compiler during compilation of program whereas Explicit type casting means the programmer explicitly type casts the variables. This is the difference implicit and explicit type casting.
Explanation:
Type casting means the conversion of one data type into another data type. There are two types of type casting. They are Implicit type casting and Explicit type casting.
<u>Implicit type casting:</u> The type casting which is done by the compiler during the compilation of a program. This occurs when we assigning smaller data type to larger data type and also both the data type are compatible. Below example clears the above concepts.
Ex:

In the above example " i " is " int " data type whereas " l " is long data type but as we assigned the value of " i " to " l ". Here " int " and " long " are compatible data types and we assigned smaller data type ( int - i ) to larger data type ( long - l ) implicit type casting occurs.
<u>Explicit type casting:</u> The type casting which is done by the programmer explicitly to convert one data type into other data type. If we want to assign a value of larger data type to smaller data type explicit type casting is required. Below example clears the above concepts.
Ex: 

In the above example " d " is " double " data type whereas " l " is " long " data type. Here we are explicitly type casting to change larger data value ( double - d ) to smaller data value ( long - l ).
Answer:
Answer to the following question is as follows;
Explanation:
Windows 7 for 100 users and Windows 8.1 for 25 users are the best options since they both enable networking and active directory, and Windows 8.1 also offers Windows server capabilities.
Winxp would therefore work for $100, but it is unsupported and has no updates.
If you wish to go with open source, you can choose Ubuntu 16 or 18 or Linux.
The answer is firewall. It is a network security device that observes inbound and outbound network traffic and chooses whether to allow or block specific traffic based on a well-defined set of security rules. Firewalls have been a first line of protection in network security for over 25 years. The firewall present a barrier between measured and secured internal networks that can be trusted and untrusted outside networks, for example the Internet. A firewall can be software, hardware, or even both.
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