1. a venturi measures flow rate using a pressure comparison between the outside and inside of a pipe.
a)true
b)false

2. an inflated balloon’s shape is determined by internal pressure and external atmospheric pressure.
a)true
b)false

1. Answer b) False
A Venturi tube uses a the pressure measurement before and after a flow restrictor, both measurements inside the pipe.

2. Answer a) True
The pressure of a gas in a volume is equally distributed on the surface of the container. So in this case, inside the balloon the pressure will be equal on the entire surface, the push force will be the same everywere and the deformation will be the same => round shape. The same principle applies on the outside, the atmospheric pressure is equally distributed on the exterior of the balloon.

Well it depends on the object or substance

Not sure but i think it's b.