Question 891873
In the future, please list each problem individually.  I've done a couple for you, but you can plug these into your calculator or an <a href = http://mathway.com>online calculator</a> to get the answers.
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The square root of -25 is 5i (imaginary number)
The square root of -.064 = 0.8i (imaginary)
The square root of +0.64 = 0.8
The square root of 361 is 19
The square root of {{{16/49}}} is {{{4/7}}}
The square root of -{{{16/49}}} is {{{4i/7}}} (imaginary)