True/False: Plate Size & Fracture Stress

[kpx001]

True or false: a large plate of a brittle material fractures at a higher applied tensile stress as compared to a small plate of the same material.

and
True or false: the critical stress for a fracture of an internal crack of length 1mm is less than the critical stress for fracture of the same material with a surface crack of length .8mm

 

[Hank_Rearden]

going by the the very basic equation for strain in any material being the change in length divided by the original length, if the stress on the object is constant then then the smaller the original length is, the less it'll strain before breaking.

I'm pretty sure about that, but I could also be horribly wrong, so my guess would be; True

 

[Astronuc]

True or false: a large plate of a brittle material fractures at a higher applied tensile stress as compared to a small plate of the same material.

and
True or false: the critical stress for a fracture of an internal crack of length 1mm is less than the critical stress for fracture of the same material with a surface crack of length .8mm

Can one determined the effects on critical stress intensity (e.g. K_Ic) and the stress intensity of the different situations/geometries?