In S.I units, the valu e of the universal gas constant is

Hard surfacing materials such as stellite

Burnishing

Both (a) and (b)

Decreases

Venturimeter is an instrument used to measure the discharge of liquid flowing in a pipe. Venturimeter consists of three parts
1. Convergent cone
2. Throat
3. Divergent cone
The length of divergent cone is made about three to four times longer than that of the divergent cone in order to avoid tendency of breaking away the stream of liquid and to minimise frictional losses.
For measuring flow by a venturimeter, it can be installed in any direction and in any location.