Does the purchas of inventory using short term credit increase a cash ratio and leave the rest constant?

What are you referring to as a "cash ratio"? Never heard of that one. Is that the percent cash is of current assets? And what do you mean by "the rest"? The rest of what?

You also need to read the red announcement at the top if this is actually homework questions.

Does the purchas of inventory using short term credit increase a cash ratio and leave the rest constant?
There is no effect if you are talking about "current ratio".

With long term borrowing you will increase your "current ratio".