Rebecca Ferguson's Height is
5ft5.5in (166 cm)
http://www.celebheights.com/s/Rebecca-Ferguson-5685.html

Women who are 5'5 to 5'8 do not tend to be referred to as leggy beauties. Do you all believe Taylor Swift is a dwarf also?
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Her listed at 5'7" is a joke, must be between 5'5"-5'6"

OMG! I pray you were joking. Most times I can tell whether somebody is screwing around, but not here.
1 foot, 70 inches?? Hahahahaha!!!!

OP meant 1.7 meter tall.

No, her height cannot be 1 foot, 70 inches.

It's a well-known fact that Tom Cruise wears elevator insoles + heels to look taller. Simon Pegg's height is 1,78, but in some pics him and Cruise look about the same height standing next to each other lol.
The lifts are visible here:
http://i.dailymail.co.uk/i/pix/2015/07/25/19/2AD6DB7E00000578-3174553-image-a-97_1437850461253.jpg
He's doing a little trick here:
http://tinyurl.com/pg9g4te
http://www.dailymail.co.uk/tvshowbiz/article-1316229/So-does-Tom-Cruise-5ft-7-stand-tall-heel-wearing-Cameron-Diaz-5ft-9.html

How did they do it when he was barefoot in the beginning?

They always make him seem taller in the movies he does compared to his coworkers

I also think that she's shorter than her listed height of 5'7" (170 cms).
Tom Cruise is 172 cms, which is just a little under 5'8".
She was the same height as him when he wearing regular shoes and she was wearing heels.
When they were both in regular shoes, she was clearly shorter than him by a few inches.
I really don't think she is more than 5'4" (163 cms).

Well she's definitely not 5'8" or more if that's what you mean.