Help on these 4 algebra questions ***

14.Evaluate the root without using a calculator, or note that the root isn't a real number.square root 8256

A.Not a real number

B.16

C.2

D.4

3. Evaluate the root without using a calculator, or note that the root isn't a real number.square root 416

A.2

B.-2

C.3

D. Not a real number

19.Write the domain of the function in interval notation.f(x)= square root 3x-12

A.(- , )

B.(- , 12)

C.(12, )

D.(-12, )

20.Two mountain bikers take off from the same place at the same time. One travels north at 4 mph, and the other travels east at 3 mph. How far apart are they after 4 hours?

A. 20 miles

B.5 miles

C.28 miles

D.14 miles