In a very low temperature which from the following will freeze at last?
A. River water
B. Canal water
C. Sea water
D. Water in a lake
A. River water
B. Canal water
C. Sea water
D. Water in a lake
A. Pyroscope
B. Pyrometer
C. Seismograph
D. Xylometer
A. Transverse
B. Electromagnetic
C. Longitudinal
D. none of these