What is 1×1-1+1×1×1-1÷1?

Answer 1

Remember My Dear Aunt Sally for order of operations. Multiply. then Divide Then Add. Then Subtract MDAS

so 1x1 = 1 and 1x1x1 = 1

So the expression becomes

1 - 1 + 1 - 1/1

1/1 = 1

so the expression simplifies to 1+ 1 - 1 -1 = 0