Answer:
Differences can be :
1. Lever is onr of the six simple machines but pulley is a simple machine which has a wheel and axle .
2. Lever is of 3 types (first class , second class , third class ) but pulley is of only 2 types
I hope this helps you
1. The successful launch of communication satellites
2.More people will be interested in studying science
But science would probably be focused on space exploration and there will probably be less scientists in other fields such as chemistry.
As we know that friction force on box is given by

here we know that

here we have
m = 12 kg

so now we have

now we will have


so it required minimum 49 N(approx) force to move the block
Answer:
15 m per second
900m per minute
54,000 per hour
Explanation:
60 divided by 4 to get per second then times 60 for per minutes
then times 60 to get per hour