No not normal.
A wired connection instead of wireless will do better - what bandwidth are you suppose to have and what does
result in Mb/sec compared to what your ISP
What kind of router and setup?
Tried other web sites? tried changing your domain name servers.
I always find downloads from Microsoft or Amazon and Apple to go very well (though downloads of Lion use to be slow).
In some cases 3rd party AV or firewalls have been to blame.
A thread around here walked through how to test your network settings, what kind of signal you are getting through your modem. Your ISP can also see if you do have trouble with access - not just this one file.
Good to hear... if you do end up wanting to put Windows on your mac to run natively, Apple calls it Boot Camp and Boot Camp assistant utility, or just as a VM... but some programs in the past "Little Snitch" was one, would interfere greatly with downloads as did one or two others. So that is always one place to look - modifications to the default firewall and such.
There is usually a help or tutorial or guide along with tech support notes.
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