Answer:
6 mols HCl
Step-by-step explanation:
(I'm an AP chemistry student but not perfect at this stuff)
you can use the Molarity=Moles/L equation here:
(6M)=(moles HCl)/(1L)
divide by 1 on both sides to isolate the moles of HCl
this gets you 6 moles HCl.
Again I'm just a student so my answer might be wrong, but this question should just require the M=mols/L equation :).