1.The density of gold is 19.3 g.cm^ -3. Which of the following statements is correct?
a - the density of 2 cm^3 of gold is 38.6g
b - the density of gold is 19.3 kg.m^ -3
c - the specific gravity of gold is 19.3g.cm^ -3
d - the specific gravity of gold is 19.3

2. If the mass of 1m^3 of air is 1.3kg, what is the standard gravity of air?
a - 1.3
b - 0.13
c - 0.013
d - 0.0013

3. Calculate the pressure at the bottom of a dam which is 5.5 m deep. Air pressure = 1.01 x 10^5 Pa.
a - 1.55 x 10^5 Pa
b - 5.56 x 10^5 PA
c - 5.39 x 10^4 Pa
d - 5.50 x 10^3 Pa

4. Calculate the effectiveness of a machine which transport a load of 175N over a distance of 10m, if the work done by the machine is 2000 Joule.
a - 87.5%
b - 0.875
c - 114%
d - 1.14