What was the main reason tanks were introduced during world war i?

Discuss the ways in which the northern and southern economies and social customs differed in the decade prior to the civil war. why are they characterized as having “two distinct societies”?

Tori is researching for her blog post about how wearing sunblock can prevent skin cancer, and she finds a page about her topic on the united states centers for disease control website at is this a reliable site for tori’s research? yes, because it is presented by a college or university no, because it is a personal opinion about the subject yes, because it is run by a governmental organization no, because it is intended to advertise a certain product

Kleenex and band-aids are prime examples of advertisement