The computers are all running Windows 10, if you're gonna ask for that.
Simply google for does windows 10 have net framework
See https://blogs.msdn.microsoft.com/astebner/2007/03/14/mailbag-what-version-of-the-net-framework-is-included-in-what-version-of-the-os/
Windows 10 (all editions) includes the .NET Framework 4.6 as an OS component, and it is installed by default. It also includes the .NET Framework 3.5 SP1 as an OS component that is not installed by default. The .NET Framework 3.5 SP1 can be added or removed via the Programs and Features control panel.
Windows 10 November 2015 Update (all editions) includes the .NET Framework 4.6.1 as an OS component, and it is installed by default. It also includes the .NET Framework 3.5 SP1 as an OS component that is not installed by default. The .NET Framework 3.5 SP1 can be added or removed via the Programs and Features control panel.
Windows 10 Anniversary Update (all editions) includes the .NET Framework 4.6.2 as an OS component, and it is installed by default. It also includes the .NET Framework 3.5 SP1 as an OS component that is not installed by default. The .NET Framework 3.5 SP1 can be added or removed via the Programs and Features control panel.
Windows 10 Creators Update (all editions) includes the .NET Framework 4.7 as an OS component, and it is installed by default. It also includes the .NET Framework 3.5 SP1 as an OS component that is not installed by default. The .NET Framework 3.5 SP1 can be added or removed via the Programs and Features control panel.
Windows 10 Fall 2017 Creators Update (all editions) includes the .NET Framework 4.7.1 as an OS component, and it is installed by default. It also includes the .NET Framework 3.5 SP1 as an OS component that is not installed by default. The .NET Framework 3.5 SP1 can be added or removed via the Programs and Features control panel.
Windows 10 April 2018 Update (all editions) includes the .NET Framework 4.7.2 as an OS component, and it is installed by default. It also includes the .NET Framework 3.5 SP1 as an OS component that is not installed by default. The .NET Framework 3.5 SP1 can be added or removed via the Programs and Features control panel.