Using the equation for period length, you get an answer of about 4.1 seconds.
Answer:
a) 
b) 
Explanation:
From the question we are told that:
Density 
Velocity of wind 
Dimension of rectangle:50 cm wide and 90 cm
Drag coefficient 
a)
Generally the equation for Force is mathematically given by



Therefore Torque



b)
Generally the equation for torque due to weight is mathematically given by

Where

Therefore




Answer:
a soft foam material because soft materials absorb sound better
The correct answer is:
c. convection.
The heating of magma and the continuous cycle of evolution of the magma creating a convection current is the reason for the evolution of Earths tectonic plates.
Explanation:
Tectonic plates are ready to move because the Earth's lithosphere has higher strength than the underlying asthenosphere. Lateral density changes in the mantle appear in convection. Plate movement is believed to be driven by a succession of the motion of the seafloor apart from the extended ridge (due to variations in topography and density of the crust.