No. He is not asking for 4 hours of work. He is asking for laser-focused, 100% productive 4 hours work. You can do additional work in the rest of the hours left

No. He is not asking for 4 hours of work. He is asking for laser-focused, 100% productive 4 hours work. You can do additional work in the rest of the hours left that not necessarily is going to require that level of focus.