Transpose the prescription

Question

-0.75DS/-3.25DCx30 to the toric form with a capstan-form surface which has a +2.50D base curve

I have had a look at that website but still struggling

Answer 1

http://www.optiboard.com/forums/showthread.php/18768-Need-Help-For-Ophthalmic-Question!
and page 30 from
http://www.optometry.co.uk/uploads/articles/949e0d09ac024c2edb6d55bad5da4d11_jalie20050225.pdf

Answer 2

Is the answer +2.50dcx120/+5.75dcx120?

Answer 3

Or is it (-6.50dcx30/-3.25dcx120)/2.5ds?