is and has/will and will have/would and would have?

[asad hussain]

Which one is correct? I think, in the first pair of brackets it would be "is", and in the second pair of brackets it would be “has”. What do you think?

Q. George and Richard decide to buy a present for their parents’ silver wedding anniversary. George agrees to pay $40 more than Richard. If the present is to cost not more than $180, what (is/will/would)(?) the greatest possible amount George (has/will have/would have) to pay?

[Tdol]

I agree about the first, but think that has/will have are both possible for the second.

[asad hussain]

Thanks for a very concise and satisfactory answer, Richard.