[Njtechdiv] Excel, working on a workbook

[Mario Brusco]

I subscribe to a mailing list where I haven't received a satisfactory 
answer, and I thought I'd give someone on the techdiv list a stab at it...

in an ongoing effort, I'm working on a workbook using Excel 2010, and 
there are 2 issues that I need help to correct.
	
the first issue is to use a formula in the last cell of a column to get 
the last value that appears in that column. for example, cell b5 is the 
last cell that has information cell b10 is to have the formula that 
specifies the range b1:b9.

the second issue is to have a summary reference cell b10 from a specific 
sheet. there are 10 sheets that have a cell b10. and not all sheets will 
have a value for the summary. if the reference to cell b10 from a sheet 
is blank, the reference should also be blank.

in clear steps, can you tell me what should the formula for b10 be, and 
what should be the reference for the summary be?