Density is directly proportional to mass. So if there's less matter inside object, its density will also reduce.
Mass= density x volume
1.3 kg/m^3 x ( 2.5x4x10) m^3
= 130 kg
C is the answer hope that helps you
Answer:
Velocity of truck will be 20.287 m /sec
Explanation:
We have given mass of the truck m = 4000 kg
Radius of the turn r = 70 m
Coefficient of friction 
Centripetal force is given 
And frictional force is equal to 
For body to be move these two forces must be equal
So 

Explanation:
SUPONIENDO QUE LA ACELERACIÓN DE LA GRAVEDAD ES 
USANDO LA SEGUNDA LEY DE NEWTON:
<em>m</em> = 80.0 N/
= 8.16 kg