Answer:The answer is A,B and C
Explanation: it can be use to learn universe behavior,it is also use for the measurements of velocity of galaxy,and is can also be use to indicate,galaxy motion.
Doppler effect,measures the speed which star and galaxy are moving away from us or towards us. It shows the color of wavelength to be either red shift or blue shift.
Answer:
(a) the blocks all had different masses.
Explanation:
The surface is smooth, therefore coefficient of friction is tending to zero.
Forces for each blocks varied from 6N to 8N to 7N to 5N
The blocks were made of different materials and different materials are going to have varying weight for the same size of block.
Answer:

Explanation:
We are given that
Mass,
Radius,r=0.8 m

Height,h=2.9 m
We have to find the angular acceleration of the cylinder.
According to question


Where



Substitute the value


Where 


Angular acceleration,
Answer: false
Explanation:
While kilograms are the unit used to measure body mass, the device used is a scale.
Hope it helps :)