What would be the formula for calculating the 'total cost' in cell $\text{'}$D$6\text{'}$ in the following spreadsheet?

spreadsheet table $02$

Question $46$ options:

$=$b$2+$c$2$

$=$sum$($b$2..$b$5)$

$=$sum$($d$6)$

$=$sum$($d$2..$d$4)$

$=$b$2*$c$2$