About 13.7 billion years ago
The Big Bang Theory states that the universe started about 13.7 billion years ago, and before that, everything was in 1 singularity.
Answer:0.69
Explanation:
Coefficient of kinetic friction=f/R=61.8/90=0.69
Answer:
They're going to increase the total resistance as 
Explanation:
If the resistors are in parallel, the potential difference is the same for each resistor. But the total current is the sum of the currents that pass through each of the resistors. Then

where

but
for 
so

where

Answer: No, water in the ocean wouldn't have tides wouldn't be as strong anymore.
Explanation:
Planes don’t have mirrors